You're missing the last line of data

[SirJohnFranklin]

You're missing the last line data around line 100:

for l in lines[3:-1]:  
    # print("line = ", l)
    f = read_line(l)
    # print("f = ", f)
    x.append(f[0])
    y.append(f[1])
    x.append(f[2])
    y.append(f[3])
    x.append(f[4])
    y.append(f[5])

Should be

for l in lines[3:]:
     [....]

I have question: I see for energy spectra strange behaviour and I cannot see where it comes from.
E.g. for this data https://www-nds.iaea.org/epics2014/ENDF/EEDL/za007000

I see:

I searched through the documentation of ENTF6 but didn't find the answer. Do you have an Idea?

[DavidWalz]

Looks like this section contains multiple measurements which need to be split.
As I'm not working in this area anymore I won't have time to implement this.

print(ENDF6.find_section(lines, MF=26, MT=536))
[' 7000.00000 13.8863718          0          0          1          0 70026536    1\n',
 ' 11.00000005.438673E-4          0          1          1          2 70026536    2\n',
 '          2          2                                             70026536    3\n',
 ' 11.5000000 1.00000000 1.0000E+11 1.00000000                       70026536    4\n',
 ' 0.0        0.0                 1          2          1          8 70026536    5\n',
 '          8          2                                             70026536    6\n',
 ' 0.0        11.5000000          0          0          4          2 70026536    7\n',
 ' .002723140 40.8026000 .027231400 40.8026000                       70026536    8\n',
 ' 0.0        12.0446000          0          0          4          2 70026536    9\n',
 ' .002723140 3.74131000 .272314000 3.67734000                       70026536   10\n',
 ' 0.0        100.000000          0          0         28         14 70026536   11\n',
 ' .100000000 .106961000 .354814000 .099538700 1.25893000 .092631800 70026536   12\n',
 '
...