script fails run with default setting on demo sound files

[xf15]

Using Praat version 6.1
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SOUND SELECTION INFO
User selected DT_Deer as the voiced endpoint
User selected DT_Tier as the voiceless endpoint

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VOT CONTINUUM INFO

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User selections
Selected an aspiration segment from DT_Tier sound
   with onset landmark at 0.05009754476503245
   and offset landmark at 0.1210087903474147

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Replicating the last 0.005 at the end of the aspiration segment
   to support the maximum length of the VOT continuum

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Marked 0.054190237498508174 as the vowel onset in the DT_Deer sound

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VOT steps 
VOT_1   0.01 
VOT_2   0.02 
VOT_3   0.03 
VOT_4   0.04 
VOT_5   0.05 
VOT_6   0.06 
VOT_7   0.07 

Added 0.05 silence at the onset of each sound
Added 3 ms aspiration at the end for blending into the vowel

Vowel-cutback information:
For each 1 ms of VOT, 0.65 ms of vowel cutback
(0.65 vowel-cutback ratio)
Maximum vowel cutback actually used: 0.046
Maximum vowel cutback duration permitted: 0.7 seconds

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Original sound F0 onset: 121.0
F0 continuum minimum:  116.0
F0 continuum maximum:  146.0
Modification declared as relative change from the original

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F0 steps: 
F0_1    116 
F0_2    121 
F0_3    126 
F0_4    131 
F0_5    136 
F0_6    141 
F0_7    146 

Pitch analysis between 65 and 275 Hz

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Aspiration intensities (dB)
aspiration_int_1    58.1 
aspiration_int_2    59.1 
aspiration_int_3    60.1 
aspiration_int_4    61.1 
aspiration_int_5    62.1 
aspiration_int_6    63.1 
aspiration_int_7    64.1 

Aspiration change (dB)
aspiration_int_change_1 -6 
aspiration_int_change_2 -5 
aspiration_int_change_3 -4 
aspiration_int_change_4 -3 
aspiration_int_change_5 -2 
aspiration_int_change_6 -1 
aspiration_int_change_7 0 

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Used 0.006 as the VOT cross-fade duration 

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Output sounds maintained natural intensity-VOT relationship
(not equalized for RMS)

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Vowel onset intensitying ramping

using praat 6.1.51 on mac 10.15

[xf15]

also endif is missing for https://github.com/ListenLab/VOT/blob/e3bdd3453c1fa094f56da51dc94605abb9956ab8/Make_VOT_Continuum_v31.txt#L669

[xf15]

i made shape_vowel_envelope_onset 0 to circumvent the error from that formula for now. i think the product works for my purpose! thank you so much for the script!