DP4 analysis using NMR descriptor file fails #79
Description
When supplying an NMR descriptor file rather than raw NMR data, the importing of the proton shifts doesn't work properly- one of the arrays used is just filled with the first shift value. Error is returned, e.g.:
**Hshifts: [6.89, 6.73, 3.81, 3.81, 3.81, 3.6, 3.6, 3.6, 2.3, 2.3, 2.3, 2.0, 2.0, 2.0]
Equivalents: []
Omits: []
Calculating DP4 probabilities...
Traceback (most recent call last):
File "/home/nmr/DP5-master/PyDP4.py", line 843, in
main(settings)
File "/home/nmr/DP5-master/PyDP4.py", line 529, in main
DP4data = DP4.InternalScaling(DP4data)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nmr/DP5-master/DP4.py", line 139, in InternalScaling
DP4data.Hscaled.append(ScaleNMR(Hshifts, Hexp))
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nmr/DP5-master/DP4.py", line 151, in ScaleNMR
slope, intercept, r_value, p_value, std_err = stats.linregress(expShifts,
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nmr/anaconda3/envs/dp5/lib/python3.11/site-packages/scipy/stats/_stats_mstats_common.py", line 157, in linregress
raise ValueError("Cannot calculate a linear regression "
ValueError: Cannot calculate a linear regression if all x values are identical**
However inspection of the variable that inputs to the regression shows it just contains 6.89,6.89,6.89....
In NMR.py we have :
exp_ind = 0
for shift ,label in zip( sortedCCalc , sortedClabels):
if label not in NMRData.Omits:
ind = tempCCalcs.index(shift)
assignedCExp[ind] = sortedCExp[exp_ind]
tempCCalcs[ind] = ''
exp_ind += 1
# Proton
exp_ind = 0
for shift,label in zip( sortedHCalc,sortedHlabels):
if label not in NMRData.Omits:
ind = tempHCalcs.index(shift)
assignedHExp[ind] = sortedHExp[exp_ind]
tempHCalcs[ind] = ''
# update isomers class
iso.Cexp = assignedCExp
iso.Hexp = assignedHExp
ie there is no increment of the index for reading the proton shifts here. Inserting exp_ind += 1 after tempHCalcs[ind] = '' solves the problem.