Conflict_LSTM
__THE REPORT TO BE ASSESED IS: Masters_project(10).pdf__
Summary
Current Version: 0.1.0
Lightweight python package implementing easy to use Convolutional LSTMs and Convolutional LSTM encoder - decoder models for use in conflict prediction.
Conflict_LSTM allows:
- The construction and training of spatially deep Convolutional LSTM encoder decoder models.
- Production of new image sequence datasets from PRIO and UCDP data.
- Analysis and Visualisation of produced results.
./Figures contains generated figures for use in report and presentation
./saved runs contains saved state dict of trained models
./training logs contains training logs of trained models
Installation
Download git repository and run $ python setup.py install inside the directory.
Requirements
The package dependancies and current requirements including versions are outlined in requirements.txt. These may be installed recursively using pip.
The project is also dependant on Cartopy for use in coordinate transforms while plotting data. Cartopy should be installed using conda, due to its own dependancy on non pip availiable distributions. The plotting functionality that requires Cartopy is isolated to map_module. If users do not wish to use the plotting functionality they may import the other modules. Note that Cartopy is not listed in the requirements.txt if downloading recursively from pip
Functionality
Functionality is split across 3 modules: latest_run, hpc_construct, and map_module.
- latest_run contains functionality to construct and train ConvLSTM encoder decoder models to be run on latest conflict prediction data.
- hpc_construct contains functionality to construct new conflict datasets and to analyse predictions. -map_module contans functionality to visualise conflict data.
Usage
The package is designed to be use for research in the field of conflict prediction. The functions are designed to be as lightweight and readily customiseable as possible. Example usecases are demonstrated in .ipynb notebooks in the examples folder.
- dataset_construction_example.ipynb deals with the construction of the dataset.
- model_training_example.ipynb outlines the construction and training of a model.
- analysis_example.ipynb demonstrates the analysis that may be performed on a now constructed model.
Documentation
Classes
LSTMunit
-
Base unit for an overall convLSTM structure.
-
Implementation of ConvLSTM in Pythorch. Used as a worker class for LSTMmain. Performs Full ConvLSTM Convolution as introduced in XXXX. Automatically uses a padding to ensure output image is of same height and width as input. Each cell takes an input the data at the current timestep Xt, and a hidden representation from the previous timestep Ht-1. Each cell outputs Ht
Attributes
input_channels: int
The number of channels in the input image tensor.
output_channels: int
The number of channels in the output image tensor following
convoluton.
kernel_size: int
The size of the kernel used in the convolutional opertation.
padding: int
The padding in each of the convolutional operations. Automatically
calculated so each convolution maintains input image dimensions.
stride: int
The stride of input convolutions.
filter_name_list: str
List of identifying filter names as used in equations from XXXX.
conv_dict: dict
nn.Module Dictionary of pytorch convolution modules, with parameters
specified by attributes listed above. Stored in Module Dict to make
accessible to pytorch autograd. See pytorch for explanation of
computational tree tracking in pytorch.
shape: int, list
List of dimensions of image input.
Wco: double, tensor
Pytorch parameter tracked tensor for use in hammard operation in
LSTM logic gates. Is a pytorch parameter to allow computational
tree tracking.
Wcf: double, tensor
Pytorch parameter tracked tensor for use in hammard operation in
LSTM logic gates. Is a pytorch parameter to allow computational
tree tracking.
Wci: double, tensor
Pytorch parameter tracked tensor for use in hammard operation in
LSTM logic gates. Is a pytorch parameter to allow computational
tree tracking.
tanh: class
Pytorch tanh class.
sig: class
Pytorch sigmoid class.Methods
-
init : Constructor method for LSTM
Parameters ---------- input_channel_no: int Number of channels of the input image in the LSTM unit hidden_channel_no: int The number of hidden channels of the image output by the unit kernel_size: int The dimension of the square convolutional kernel used in the forward method stride: int depractated -
forward : Pytorch module forward method.
Calculates a forward pass of the LSTMunit. Takes in the sequence input at a timestep, and previous hidden states and cell memories and returns the new hidden state and cell memory, as according to the outline in XXXX. Parameters ---------- x: tensor, double Pytorch tensor of dimensions shape, as specified in class constructor tensor should be 3 dimensional tensor of dimensions (input channels, height, width). x is the image at a single step of an image sequence h: tensor, double Pytorch tensor of dimensions (output channels, height, width). h is the output hidden state from the last step in the LSTM sequence c: tensor, double Pytorch tensor of dimensions (output channels, height, width). h is the output cell memory state from the last step in the LSTM sequence Returns ------- h_t: tensor, double Tensor of the new hidden state for the current timestep, Pytorch tensor of dimensions (output channels, height, width) c_t: tensor, double Tensor of the new cell memory state for the current tinestep, Pytorch tensor of dimensions (output channels, height, width)LSTMmain
-
Implementation of ConvLSTM for use both standalone and as part of Encoder Decoder Models
-
Instances and iterates over LSTMunits
Attributes
input_channel_no: int
The number of input channels in the input image sequence
hidden_channel_no: int
The number of channels in the output image sequence
kernel_size: int
The size of the kernel used in the convolutional opertation.
test_input: int, list
Describes the number of hidden channeels in the layers of the multilayer
ConvLSTM. Is a list of minimum length 1. i.e a ConvLSTM with 3 layers
with 2 hidden states in each would have test_input = [2,2,2]
copy_bool : boolean, list
List of booleans for each layer of the ConvLSTM specifying if a hidden
state is to be copied in as the initial hidden state of the layer. This
is for use in encoder - decoder architectures
debug: boolean
Controls print statements for debuggingMethods
-
init : constructor method
-
Forward: Forward method of the ConvLSTM
Takes a sequence of image tensors and returns the hidden state output of the final LSTM layer. Takes in hidden state tensors for intermediate layers to allow for use in decoder models. The method can copy out specified hidden states to allow for use in encoder models. Parameters ---------- x : double, tensor Input image sequence tensor, of dimensions (minibatch size, sequence length, channels, height, width) copy_in: list of double tensors List of hidden state tensors to be copied in to LSTM layers specified by copy_bool. copy_in should only contain the hidden state tensors for the require a copied in state. The states should be arranged in order, so that the hidden state to be copied into the first layer is first. copy_out: boolean, list List of booleans specifying which layer hidden states are to be copied out due to being required to be passed to a decoder. Returns ------- x: double, tensor Tensor of the hidden state outputs of the final LSTM layer. x is of shape (minibatch size, image sequence length, final hidden channel number, height, width) internal_outputs: tensor, list Last hidden states of layers specified by copy_out. To be used in encoder LSTM to be copied into decoder LSTM as the copy_in parameter
LSTMencdec_onestep
-
Class to allow easy construction of ConvLSTM Encoder-Decoder models
Constructs ConvLSTM encoder - decoder models using LSTMmain. Takes structure argument to specify architecture of initialised model. The structure is a 2D numpy array. The top row of the array defines the encoder, the bottom row defines the encoder. Non zero values in the encoder and decoder rows define the number of layers and the hidden channel number for each layer of the encoder decoder model. 0 values after a positive in an encoder row denote the end of the encoder. 0 values precede the hidden channel specification for the decoder. A column overlap between two non zero values means that the hidden states are copied out of the corresponding encoder layer and into the decoder model. An encoder that has hidden channels of size 6, and 12, and decoder that reduces the prediction to 6 channels symmetrically would be input as: structure = [[6,12,0,], [0,12,6]]
Attributes
Structure: int, list
"""Methods
-
init: Constructor for LSTMencdec
Constructs two intances of LSTMmain, one encoder and one decoder. passes structure argument to input_test function to produce the analytics of the functions. Parameters ---------- structure: array of ints 2d array of ints used to specify structure of encoder decoder. The top row of the array defines the encoder, the second row of the array defines the decoder. Non zero digits signify then number of channels in the hidden state for each layer. Zero digits specify the end of the encoder, and are used before the initial digits of the decoder as a placeholder. Vertical overlap of non zero digits specifies that the hidden state of the encoder layer will be copied as the initial state into the corresponding decoder layer. An example outputting an image sequence of 5 hidden layers is shown. structure = [[6,12,24,0,0,0], [0,0,24,12,8,5]]. input_channels: int The number of channels of each image in the image input sequence to the encoder decoder. kernel_size: int, optional The size of the convolution kernel to be used in the encoder and decoder layers. debug: bool, optional Switch to turn off debugging print statements. -
input_test : Checks and extracts information from the given structure argument
Returns ------- enc_shape: list of int shape argument specifying hidden layers of the encoder to be passed to LSTMmain constructor. dec_shape: list of int enc_shape: list of int shape argument specifying hidden layers of the decoder to be passed to LSTMmain constructor. enc_overlap: list of bool List of boolean values denoting whether each layer of the encoder overlaps with a decoder layer in the structure input and thus should copy out. To be passed to the LSTMmain 'copy_bool' argument dec_overlap: list of bool List of boolean values denoting whether each layer of the decoder overlaps with an encoder layer in the input and thus should copy in a hidden layer. To be passed to the LSTMmain 'copy_bool' argument. -
Forward : Forward method of LSTMencdec
Takes input image sequence produces a prediction of the next image in the sequence frame using a conditional LSTM encoder decoder structure Parameters ---------- x: tensor of doubles Pytorch tensor of input image sequences. should be of size (minibatch size, sequence length, channels, height, width) Returns ------- tensor: Tensor image prediction of size (minibatch size, sequence length, channels, height, width) """HDF5Dataset_with_avgs
-
dataset wrapper for hdf5 dataset to allow for lazy loading of data. This allows ram to be conserved. As the hdf5 dataset is not partitioned into test and validation sets, the dataset takes a shuffled list of indices to allow specification of training and validation sets. The dataet lazy loads from hdf5 datasets and applies standard score normalisation in the getitem method.
Methods
-
init
Parameters
path: str filepath to hdf5 dataset to be loaded. index_map: list of ints List of shuffled indices. Allows shuffling of hdf5 dataset once extracted. The value at the list index is the mapped sample extracted from the hdf5 dataset. e.g A index list of [2,1,3] would mean that if the 2nd value was called via getitem by a dataloader, the 1st value in the dataframe would be returned. This provides less overhead than shuffling each selection. avg: list of floats List of averages for every channel in image sequence loaded. Length should equal number of channels in dataset image sequence std: list of floats List of standard deviations for every channel in image sequence loaded. Length should equal number of channels in dataset image sequence. application_boolean: list of bools List of bools indicating whether standard score normalisation is to be applied to each layer. Length should equal number of channels in dataset image sequence.
"""
Functions
Initialise_dataset_HDF5_full
-Returns datasets for training and validation.
-Loads hdf5 custom dataset and utilising a shuffle split, dividing according to specified validation fraction.
Parameters
----------
dataset: str
filename / path to hdf5 file.
valid_frac: float
fraction of the loaded dataset to portion to validation
dataset_length: int
number of samples in the dataset to be loaded.
avg: list of floats
Averages for each predictor channel in the input image sequences
std: list of floats
Standard deviation for each predictor channel in the input image sequence
application_boolean: list of bools
List of booleans specifying if which predictor channels should be standard
score normalised
Returns
-------
train_dataset: Pytorch dataset
Dataset containing shuffled subset of samples for training
validation_dataset: Pytorch dataset
Dataset containing shuffled subset of samples for validationtrain_enc_dec
-Training function for encoder decoder models.
Parameters
----------
model: pytorch module
Input model to be trained. Model should be end to end differentiable,
and be inherited from nn.Module. model should be sent to the GPU prior
to training, using model.cuda() or model.to(device)
optimizer: pytorch optimizer.
Pytorch optimizer to step model function. Adam / AMSGrad is recommended
dataloader: pytorch dataloader
Pytorch dataloader initialised with hdf5 averaged datasets
loss_func: pytorch loss function
Pytorch loss function
verbose: bool
Controls progress printing during training.
Returns
-------
model: pytorch module
returns the trained model after one epoch, i.e exposure to every piece
of data in the dataset.
tot_loss: float
Average loss per sample for the training epochwrapper_full
-Training wrapper for LSTM encoder decoder models.
-Trains supplied model using train_enc_dec fucntions. Logs model hyperparameters and trainging and validation losses in csv training log. Saves the model and optimiser state dictionaries after each epoch in order to allow for easy checkpointing.
Parameters
----------
name: str
filename to save CSV training logs as.
optimizer: pytorch optimizer
The desired optimizer needed to train the model
structure: array of ints
Structure argument to be passed to lstmencdec. See LSTMencdec for explanation
of structure format.
loss_func: pytorch module
Loss function to be used to calculate training and validation losses.
The loss should be a CLASS instance of the pytorch loss function, not
a functinal implementation.
avg: list of floats
List of averages for every channel in image sequence loaded. Length should
equal number of channels in dataset image sequence
std: list of floats
List of standard deviations for every channel in image sequence loaded.
Length should equal number of channels in dataset image sequence.
application_boolean: list of bools
List of bools indicating whether standard score normalisation is to be
applied to each layer. Length should equal number of channels in dataset
image sequence.
lr: float
Learning rate for the optimizer
epochs: int
Number of epochs to train the model for
kernel_size: int
Size of convolution kernel for the LSTMencoderdecoder
batch_size: int
Number of samples in each training minibatch.
Returns
-------
bool:
indicates if training has been completed.test_image_save
"""Saves comparison between prediction of the given model and ground truth.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset from which input sequence to be visualised is stored
name: str
Filename to save visualised comparison in.
sample: int
Sample of the input dataset to be predicted.
Returns
-------
fig:
Matplotlib figure to be manipulated outside of program.
"""f1
"""Produces average F1 score for each image prediction in the dataset.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset from which input sequence to be visualised is stored
avg: str
method of averaging over each multilabel image. see sklearn.metrics.f1_score
for specification of the average key types
Returns
-------
list:
List of scores for each image sequence prediction
"""Metrics
"""Calculate TN, FN, TP, FP, precision, recall and f1 score.
Calculates the true negative, false negative, true positive, false positive,
precison, recall, and multilabel f_1 score for the model predictions of a
supplied data sample. The F1 score is calculated according to XXXX. To offset
bias in multilabel sampling. Produces CSV storing performance metrics for
later analysis.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset in which input sequence to be visualised is stored.
name: str
filename to store metrics CSV under.
verbose: bool
Controls print output of metrics
save: bool
controls whether metrics will be saved in csv
Returns
-------
list:
true negative, false negative, true positive, false positive,
precison, recall, and multilabel f_1 score for the model predictions.
"""Area_under_curve_metrics
"""Calculates the Area Under the Reciever Operator Charactersitc (AUROC) curve and the Area Under the Precision Recall (AUPR) curve. Uses average_precision_score to calculate AUPR.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset in which input sequence to be visualised is stored.
name: str
filename to store metrics CSV under.
verbose: bool
Controls print output of metrics
save: bool
controls whether metrics will be saved in csv
Returns
-------
list:
list of [AUROC, AUPR]
"""brier_score
"""Calculates the average brier score for each prediction. Saves prediction in metrics csv.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset in which input sequence to be visualised is stored.
name: str
filename to store metrics CSV under.
verbose: bool
Controls print output of metrics
save: bool
controls whether metrics will be saved in csv
Returns
-------
float:
brier score.
"""full_metrics
"""extracts all performance metrics from one data sample.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset in which input sequence to be visualised is stored.
name: str
filename to store metrics CSV under.
"""curves
"""PLots ROC curves for diagonal pixels in image prediction
Plots ROC curves for diagonal pixels in the image predictions.This is done
to reduce overcrowding of plots.
Parameters
----------
model:
Trained model to visualise prediction of.
train_loader:
Dataloader of dataset in which input sequence to be visualised is stored.
"""analytics
"""Loads given state dict and extracts metrics.
Uses test_image save and full_metrics to compile metric report in csv and
to visualise prediction, from loaded pretrained model statedict. NOTE THAT
STRUCTURE AND KERNEL SIZE SHOULD BE THE SAME AS THE TRAINING MODEL.
Parameters
----------
structure: array of int
Structure to initialise the LSTMencdec_onestep model. See LSTMencdec_onestep
for explanation.
kernel_size: int
Size of the convolutional kernel used in the model
model_path: str
relative path to saved model state dict
dataset_path: str
relative path to dataset to test on
dataset_length: int
Number of samples in dataset.
avg_path: str
relative path to dataset averages
std_path: str
relative path to dataset standard deviations
sample: int
the specific dataset sample to be visualised. Note this does not effect
how the performance metrics are calculated, which are extracted from all
samples
Returns
-------
bool:
True
"""
### construct_layer
"""Constructs single global parameter map of PRIO encoded variables
Takes input dataframe of either PRIO or UCDP data. Produces 360 x 720 array
prio grid single layer representation of conflict predictor specified by
key input.
Parameters
----------
dataframe: Pandas Dataframe
Dataframe of either UCDP or PRIO data, with column index of prio grid cells
for each entry. Data is found at PRIO or UCDP websites XXXX.
key: str
Dataframe key for chosen predictor to be extracted and spatially
represented in the output array.
prio_key: str
Dataframe key for the column noting the PRIO grid cell location of each
entry. For UCDP csvs prio_key = 'priogrid_gid', for PRIO csvs prio_key
= 'gid'
debug: bool
controls debugging print statements
Returns
-------
array:
array of height 360, width 720 containing the selected parameter arranged
spatially into the corresponding PRIO grid cell.
"""
### construct_combined_sequence
"""Constructs Series of global representations of PRIO and UCDP conflict predictors
Constructs Series of global representations of PRIO and UCDP conflict
predictors in an image array format. Image representations of the selected
conflict predictors at each month between start and stop dates are predicted
into a global prio grid represenation of size 360 x 720. Each selected predictor
is allocated an image channel. The output is returned as size: (months,
predictor number, 360, 720). The output is of size 360 x 720 due to each
prio grid cell being of dimensions 0.5 degrees lattitude and longitude.
Parameters
----------
dataframe_prio: pandas DataFrame
Dataframe constructecd from PRIO grid data CSV in the format supplied
by the PRIO grid Project.
dataframe_ucdp: pandas DataFrame
Dataframe constructecd from UCDP grid data CSV in the format supplied
by the UCDP grid Project.
key_list_prio: str, list
List of Dataframe keys for desired predictors to extract from the PRIO
Dataframe to represent spatially per prio grid cell.
key_list_ucdp: str, list
List of Dataframe keys for desired predictors to extract from the UCDP
Dataframe to represent spatially per prio grid cell.
start: int, list
Representation of data extraction start date. in [y,m,d] format
stop: int, list
Representation of data extraction finish date. in [y,m,d] format
Returns
-------
array:
returns array of size (months, channels, height, width). The array
is a sequence of global images of Conflict predictors for each month
between specified start and end dates. Each channel represents a
specified conflict predictor. Each pixel corresponds to one PRIO grid
cell.
"""
### construct_channels
"""Constructs global parameter layer of multiple specified conflict predictors
Constructs global parameter layer of multiple specified conflict predictors
for use in Construct_Combined_sequence. Takes dataframe of either PRIO or
UCDP conflict data for a single month and selects predictors for channels
based on the key_list argument.
Parameters
----------
dataframe: pandas Dataframe
Dataframe of conflict data, constructed from CSV datasets from PRIO or
UCDP. Must have a column of PRIO grid cell values for each Predictor
value.
key_list: str, list
List of Dataframe keys for which parameters are extracted into image
layers.
prio_key: str
Dataframe key for the PRIO grid column. For PRIO converted datasets the
key is 'gid'. For UCDP converted datasets the key is 'priogrid_gid'
Returns
-------
array:
image representation of global values of conflict data. Returns image of
dimension (len(key_list, 360, 720). Each pixel represents the predictor
value at a particular grid cell.
"""
### random_pixel_bounds
"""Returns range of indices to extract a randomly placed square of size
chuksize in which the specified entry of the overall array is captured
Function returns 4 parameters: i_lower, i_upper, j_lower, j_upper which define
the bounds of the square region to be extracted. structured so the extracted
region may be defined as extracted = target[i_lower:i_upper, j_lower:j_upper]
Parameters
----------
i: int
i index of the array entry to be captured
j: int
j index of the array entry to be captured
chunk_size: int
side length of the square to be cut out of the array.
Returns
-------
i_lower: int
Lower i index for the random square placed over the targetted event.
i_upper: int
Upper i index for the random square placed over the targetted event.
j_lower: int
Lower j index for the random square placed over the targetted event.
j_upper: int
Upper j index for the random square placed over the targetted event.
"""
### random_grid_selection
"""Extracts conflict image sequence samples for a given monnth.
Produces conflict image sequence samples for each month from an input global
image sequnce produced using construct_combined_sequence. Takes input image
sequence of global representations of PRIO grid conflict predictors and extracts
image sequences of events. Events may be clustered to remove outliers via
Kmeans clustering. A square of side length chunksize surrounding each non zero
grid cell in the first channel of each month's prio image is randomly placed
and the image for that month is extracted as the truth value for prediction.
The preceding 10 months events are extracted in the same manner as the input.
If the extracted preceding sequence contains more than min_events non zero
values in the first image channel (total) the preceding image sequence and
ground truth prediction are kept.
Parameters
----------
image: array
Input array of sequences of global representations of the PRIO conflict
predictors. This should be produced by the construct_combined_sequence
function. The array should be of size (months, channels, 360, 720)
sequence_step: int
The chosen month from which the prediction ground truth is extracted,
and which precedes the 10 predicting months, from which the image
prediction sequence will be extracted.
chunk_size: int
side length of the square to be cut out of the array.
draws: int
The number of times each event is to be randomly sampled. i.e how many
data samples are extracted per viable event
cluster: bool
Controls whether events will be subject to outlier detection before
being sampled. Enabling removes small, isolated events.
min_events: int
The total number of conflict events required in the prediction sequence
for a datasample to be accepted. 25 works as an optimum value for filtering
out small events with little spatial dependancy
debug: bool
controls debugging print statements.
Returns
-------
tuple:
Returns tuple of two numpy arrays. The first contains an array of sampled
prediction sequences, the second contains an array of ground truth next
steps in the conflict sequence. The prediction sequence array is of dimensions
(number of samples, sequence steps, channels, chunksize, chunksize)
The array of ground truths is of size (number of samples, chunksize,
chunksize)
"""
### full_dataset_h5py
"""Produces h5py Dataset of conflict image sequences, and the prediction ground truth
Uses random_grid_selection to extract conflict image prediction sequences
and the next step in the sequence (i.e the image to be predicted). The produced
image sequences are stored in a hdf5 dataset to allow lazy loading of image
sequences. The keys 'predictor' and 'truth' are used to store the predictors
and prediction ground truths. The data selected is stored as meta data attributes
on the hdf5 dataset.
Parameters
----------
image: array
Input array of sequences of global representations of the PRIO conflict
predictors. This should be produced by the construct_combined_sequence
function. The array should be of size (months, channels, 360, 720)
filename: str
name of hdf5 file to be saved.
key_list_prio: str, list
List of PRIO data keys selected
key_list_ucdp: str, list
List of UCDP data keys selected
chunk_size: int
dimensions of images in image sequence to be extracted.
draws: int
Number of times an event is to be randomly sampled
min_events: int
Threshold of conflict events in image sequence that the image sequence
must meet to be added to the dataset.
debug: bool
Switch for turning on debugging print options
"""
### find_avg_lazy_load
"""Extracts average and std from produced hdf5 datasets
Uses hdf5 lazy loading to subdivide produced image sequence datasets and extract
an overall average, when the produced datasets are too large to naively average
and find the standard deviation for.
Parameters
----------
data: hdf5 file
Takes loaded hdf5 file. File should have two datasets, accessible via
the keys: 'predictor' and 'truth'. Full_dataset_h5py produces suitable
files.
div: int
The number of datasamples to average over at a time.
Returns
-------
avg: list of int
List of averages for each channel in the input image sequence dataset
std: List of int
List of standard deviations for each channel in the inout image sequence
dataset.
"""
### construct_dataset
"""Produces image sequence dataset from input of conflict predictor dataframes
Short pipeline function for construct_combined_sequence, and full_dataset_h5py.
Parameters
----------
filename: str
The filename underwhich the produced hdf5 image sequence dataset is saved
data_prio: pandas DataFrame
Dataframe of PRIO grid v2 data
data_ucdp: pandas Dataframe
Dataframe of UCDP conflict data
key_list_prio: list of str
List of strings passed to dataframe to select chosen conflict predictors
key_list_ucdp: list of str
List of strings passed to dataframe to select chosen conflict predictors
start: list of int
start date of data to be selected in int [y,m,d] format
stop: str
stop date of data to be selected in "yyyy-mm-dd" format.
"""