在模式之后打印所有条目，但不包括模式-AWK

Question

Consider the following input file

* Z1 Z2 A1pre A2pre A1post A2post I1pre I2pre I1gs I2gs Eexc1 Eexc2 n1 n2 TKEpre TKEpost  
* Z1: Atomic number of first fragment
* Z2: Atomic number of second fragment
* A1pre: Pre-neutron mass number of first fragment
* A2pre: Pre-neutron mass number of second fragment
* A1post: Post-neutron mass number of first fragment
* A2post: Post-neutron mass number of second fragment
* I1pre: Spin of first fragment after scission
* I2pre: Spin of second fragment after scission
* I1gs: Ground-state spin of first fragment
* I2gs: Ground-state spin of second fragment
* Eexc1: Excitation energy of first fragment [MeV]
* Eexc2: Excitation energy of second fragment [MeV]
* n1: Prompt neutrons emitted from first fragment
* n2: Primpt neutrons emitted from second fragment
* TKEpre: Pre-neutron total kinetic energy [MeV]
* TKEpost: Post-neutron total kinetic energy [MeV]

* Calculation with nominal model parameters
 38 54  97 138  94 136  5.5  9.0  0.0  0.0  21.72  14.78  3  2 159.43 156.00 
 39 53 101 134  99 133  2.5  4.0  2.5  3.5  17.12  12.93  2  1 166.45 161.75 
 36 56  92 143  91 143  3.0 11.5  2.5  2.5  12.27   7.81  1  0 170.00 168.44 
 38 54  93 142  92 141  3.5  7.0  0.0  2.5  13.94   9.81  1  1 168.95 163.96 
 40 52  99 136  98 135  2.5  6.0  0.0  3.5   9.28  13.10  1  1 177.04 172.75 
 40 52 100 135  98 134  0.0  6.5  0.0  0.0  14.74  10.13  2  1 176.61 173.55

What I want to do is to print specific columns following the Calculation with nominal model parameters pattern.

So far I've tried

awk '{/Calculation with nominal model parameters/;line=FNR}{for(i=0;i<=NR-19;++i){getline;print $5 "\t" $6 "\t" $16 "\t" $16*$6/($5+$6) "\t" $16*$5/($5+$6)}}{print line}' input

and my output is more or less what I want

88      144     159.10  98.7517 60.3483
87      146     164.87  103.309 61.5609
92      141     163.96  99.2204 64.7396
98      135     172.75  100.091 72.6588
98      134     173.55  100.24  73.3099
98      134     173.55  100.24  73.3099
19

As you can see the two last lines are identical. My goal is to avoid calculating the same thing twice. To achieve that I thought that I should finish the loop after NR-NFR_pattern , that's why I used line variable.

The weird thing is that even if I hardcode the pattern's NFR I don't get the desired output.

The weirdest thing is that if I replace the hardcoded NFR with the variable that has the NFR information ie

awk '{/Calculation with nominal model parameters/;line=FNR}{for(i=0;i<=NR-line;++i){getline;print $5 "\t" $6 "\t" $16 "\t" $16*$6/($5+$6) "\t" $16*$5/($5+$6)}}' input

I get the error

awk: (FILENAME=input FNR=2) fatal: division by zero attempted

Any idea how to solve this?

Answer 1

What you are missing, I think, is that getline changes NR:

getline               Set $0 from next input record; set NF, NR, FNR, RT.

I wouldn't use getline at all.

awk 'isdata{print $5 "\t" $6 "\t" $16 "\t" $16*$6/($5+$6) "\t" $16*$5/($5+$6)}
  /Calculation with nominal model parameters/{isdata="yes"}' input

I get:

94      136     156.00  92.2435 63.7565
99      133     161.75  92.7274 69.0226
91      143     168.44  102.936 65.5044
92      141     163.96  99.2204 64.7396
98      135     172.75  100.091 72.6588
98      134     173.55  100.24  73.3099