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lkilcher / dolfyn

A library for oceanographic doppler instruments such as Acoustic Doppler Profilers (ADPs, ADCPs) and Acoustic Doppler Velocimeters (ADVs).
BSD 3-Clause "New" or "Revised" License
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error: unpack requires a string argument of length 2 when reading adcp file #6

Closed rmduarte closed 7 years ago

rmduarte commented 7 years ago

Dear Levi,

After correcting the problem with the nanmean import, we get the following error when trying to read a adcp binary file:

In [23]: data = apm.read_rdi('SMADCP-FEM-Brehat-1.000')

error Traceback (most recent call last)

in () ----> 1 data = apm.read_rdi('SMADCP-FEM-Brehat-1.000') C:\Données brutes\dolfyn\dolfyn\adp\api.py in read_rdi(fname, nens) 14 15 def read_rdi(fname, nens=None): ---> 16 with adcp_loader(fname) as ldr: 17 dat = ldr.load_data(nens=nens) 18 return dat C:\Données brutes\dolfyn\dolfyn\adp\_readbin.py in __init__(self, fname, navg, a vg_func) 597 #self.f=io.npfile(fname,'r','l') 598 self.f = bin_reader(fname) --> 599 self.read_hdr() 600 self.read_cfg() 601 # Seek back to the beginning of the file: C:\Données brutes\dolfyn\dolfyn\adp\_readbin.py in read_hdr(self) 480 cfgid = list(fd.read_ui8(2)) 481 nread = 0 --> 482 while (cfgid[0] != 127 | cfgid[1] != 127) | (not self.checkheade r()): 483 nextbyte = fd.read_ui8(1) 484 pos = fd.tell() C:\Données brutes\dolfyn\dolfyn\adp\_readbin.py in checkheader(self) 770 if numbytes > 0: 771 fd.seek(numbytes - 2, 1) --> 772 cfgid = fd.read_ui8(2) 773 #### sloppy code: 774 if len(cfgid) == 2: C:\Données brutes\dolfyn\dolfyn\adp\_read_bin.py in read_ui8(self, n) 164 165 def read_ui8(self, n): --> 166 return self.read(n, 'B') 167 168 def read_float(self, n): C:\Données brutes\dolfyn\dolfyn\adp\_read_bin.py in read(self, n, frmt) 161 return unpack(self.endian + frmt * n, val)[0] 162 else: --> 163 return np.array(unpack(self.endian + frmt * n, val)) 164 165 def read_ui8(self, n): error: unpack requires a string argument of length 2 Do you have any idea? We can send you a data file to test the code. Best regards, Rui Duarte
rmduarte commented 7 years ago

We are using Anaconda 4.2.0 and windows 7.

Thanks

lkilcher commented 7 years ago

Which Python version are you using? It looks like Anaconda 4.2.0 offers a choice between Python 3.5 and 2.7.

rmduarte commented 7 years ago

Sorry, Python 2.7

lkilcher commented 7 years ago

Well, this is very strange. I am not getting the error you have indicated above, but I am getting a different one. Regarding the error you've indicated above, is there any other text printed to the console prior to the traceback? If so, can you post that text as well? Are you sure the file you're using is the same one Jean-Francois sent me? The one I have is 2078507008 bytes long (~1.9GB).

Regarding the error I'm getting: this file has a different header than other RDI ADCPs I've typically worked with. Can you let me know the model name/number of the instrument, and any software you used to configure the instrument, read data from the instrument, or post-process the data?

lkilcher commented 7 years ago

OK, I resolved this with commit e59e37f. It had to do with a difference in the way that Windows reads files compared to unix. I needed to add a little 'b' to the open() call. I wonder how many people have tried to use this code to load files in windows, and haven't been able to? This took ENTIRELY TOO LONG to figure out! Though, I suppose I've mostly been trying to figure out the header-discrepancy issue, which is now covered in issue #7.