lheutils 0.0.7

Various CLI utilities for handling LHE files

lheutils v0.0.7

A collection of utilities for working with LHE files.

Installation

pip install lheutils

CLI Programs

Program	Description
lhe2lhe	Convert LHE files with different compression and weight format options.
lhecheck	Validate LHE files and check momentum conservation.
lhediff	Compare two LHE files and report differences.
lhefilter	Filter LHE files based on process ID, particle PDG IDs, and event numbers.
lhefix	Fix common issues in LHE files.
lheinfo	Display information about LHE files.
lhemerge	Merge LHE files with identical initialization sections (inverse of lhesplit).
lheshow	Display specific events or init block from LHE files.
lhesplit	Split LHE events from input file into multiple output files.
lhestack	Stack multiple LHE files into a single file.
lheunstack	Split a single LHE file by process ID into separate files (inverse of lhestack).
lhevalidate	Validate LHE files against the LHE XML schema.

Examples

More details can be found by running each program with the --help option.

Filtering

Get the first event with two gluons in the initial state:

$ lhefilter  pwgevents-0001.lhe --incoming-a 21 --incoming-b 21 --max-events 1
<LesHouchesEvents version="3.0">
<init>
   2212   2212  4.0000000e+03  4.0000000e+03    -1    -1    -1    -1    -4     1
 1.3255800e+01  5.9743900e-01  1.0000000e+00  10001
<initrwgt /></init>
<event>
  5  10001 -1.9892700000e+01  3.8913200000e+00 -1.0000000000e+00  2.5869900000e-01
   21  -1   0   0 503 501  0.00000000e+00  0.00000000e+00  2.20685469e+02  2.20685469e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   21  -1   0   0 502 512  0.00000000e+00  0.00000000e+00 -4.74395615e+02  4.74395615e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   25   1   1   2   0   0  8.07980331e-01  3.58616348e+00  2.02904340e+02  2.38346235e+02  1.25000972e+02  0.0000e+00  9.0000e+00
   21   1   1   2 502 501 -4.44099588e+00 -2.19203006e+00 -1.25758039e+02  1.25855520e+02  2.33601546e-06  0.0000e+00  9.0000e+00
   21   1   1   2 503 512  3.63301555e+00 -1.39413342e+00 -3.30856446e+02  3.30879329e+02  3.81469727e-06  0.0000e+00  9.0000e+00
</event>
</LesHouchesEvents>

Information

Display general information about an LHE file:

$ lheinfo pwgevents-0500.lhe
------------------------------------------------------------
File: pwgevents-0500.lhe
Beam A: 2212 (PDF: -1) @ 4000.0 GeV
Beam B: 2212 (PDF: -1) @ 4000.0 GeV
Number of events: 100000 (negative: 16.72%)
Process 10001 cross-section: (1.326e+01 +- 5.974e-01) pb
  [21, 21] -> [21, 21, 25]: 65,542 events (65.5%, negative: 18.83%)
  [2, 21] -> [2, 21, 25]: 13,076 events (13.1%, negative: 14.51%)
  [1, 21] -> [1, 21, 25]: 6,934 events (6.9%, negative: 13.37%)
  [-1, 21] -> [-1, 21, 25]: 2,232 events (2.2%, negative: 14.83%)
  [-2, 21] -> [-2, 21, 25]: 1,944 events (1.9%, negative: 13.01%)
  [3, 21] -> [3, 21, 25]: 1,286 events (1.3%, negative: 12.44%)
  [-3, 21] -> [-3, 21, 25]: 1,265 events (1.3%, negative: 11.15%)
  [-4, 21] -> [-4, 21, 25]: 807 events (0.8%, negative: 12.27%)
  [4, 21] -> [4, 21, 25]: 796 events (0.8%, negative: 12.19%)
...

Remove negative weight events from an LHE file and display summary information:

$ lhefilter --negative-weights pwgevents-0500.lhe | lheinfo
------------------------------------------------------------
File: <stdin>
Beam A: 2212 (PDF: -1) @ 4000.0 GeV
Beam B: 2212 (PDF: -1) @ 4000.0 GeV
Number of events: 83276 (negative: 0.00%)
Process 10001 cross-section: (1.326e+01 +- 5.974e-01) pb
  [21, 21] -> [21, 21, 25]: 53,203 events (63.9%, negative: 0.00%)
  [2, 21] -> [2, 21, 25]: 11,179 events (13.4%, negative: 0.00%)
  [1, 21] -> [1, 21, 25]: 6,007 events (7.2%, negative: 0.00%)
  [-1, 21] -> [-1, 21, 25]: 1,901 events (2.3%, negative: 0.00%)
  [-2, 21] -> [-2, 21, 25]: 1,691 events (2.0%, negative: 0.00%)
  [3, 21] -> [3, 21, 25]: 1,126 events (1.4%, negative: 0.00%)
  [-3, 21] -> [-3, 21, 25]: 1,124 events (1.3%, negative: 0.00%)
...

Formatting

Switching formats via lhe2lhe, starting from the first event in pwgevents-0001.lhe:

$ lhefilter --max-events 1  pwgevents-0001.lhe
<LesHouchesEvents version="3.0">
<init>
   2212   2212  4.0000000e+03  4.0000000e+03    -1    -1    -1    -1    -4     1
 1.3255800e+01  5.9743900e-01  1.0000000e+00  10001
<initrwgt /></init>
<event>
  5  10001  1.9892700000e+01  1.9026000000e+01 -1.0000000000e+00  1.6423900000e-01
   21  -1   0   0 501 502  0.00000000e+00  0.00000000e+00  9.59159976e+01  9.59159976e+01  0.00000000e+00  0.0000e+00  9.0000e+00
   -3  -1   0   0   0 511  0.00000000e+00  0.00000000e+00 -2.72494064e+02  2.72494064e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   25   1   1   2   0   0  4.09599828e+01  7.10971103e+00  4.31925771e+01  1.38634178e+02  1.25002274e+02  0.0000e+00  9.0000e+00
   -3   1   1   2   0 502 -3.20825130e+01  1.03220177e+01 -1.96527493e+02  1.99396307e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   21   1   1   2 501 511 -8.87746976e+00 -1.74317287e+01 -2.32431503e+01  3.03795766e+01  4.76837158e-07  0.0000e+00  9.0000e+00
</event>
</LesHouchesEvents>

appending the LHE event weight to the rwgt section:

$ lhefilter --max-events 1  pwgevents-0001.lhe  | lhe2lhe --weight-format "rwgt" --append-lhe-weight default default default
<LesHouchesEvents version="3.0">
<init>
   2212   2212  4.0000000e+03  4.0000000e+03    -1    -1    -1    -1    -4     1
 1.3255800e+01  5.9743900e-01  1.0000000e+00  10001
<initrwgt>
  <weightgroup name="default">
    <weight id="default">default</weight>
  </weightgroup>
</initrwgt>
</init>
<event>
  5  10001  1.9892700000e+01  1.9026000000e+01 -1.0000000000e+00  1.6423900000e-01
   21  -1   0   0 501 502  0.00000000e+00  0.00000000e+00  9.59159976e+01  9.59159976e+01  0.00000000e+00  0.0000e+00  9.0000e+00
   -3  -1   0   0   0 511  0.00000000e+00  0.00000000e+00 -2.72494064e+02  2.72494064e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   25   1   1   2   0   0  4.09599828e+01  7.10971103e+00  4.31925771e+01  1.38634178e+02  1.25002274e+02  0.0000e+00  9.0000e+00
   -3   1   1   2   0 502 -3.20825130e+01  1.03220177e+01 -1.96527493e+02  1.99396307e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   21   1   1   2 501 511 -8.87746976e+00 -1.74317287e+01 -2.32431503e+01  3.03795766e+01  4.76837158e-07  0.0000e+00  9.0000e+00
<rwgt>
 <wgt id='default'> 1.9893e+01</wgt>
</rwgt>
</event>
</LesHouchesEvents>

and finally moving the weight to the init-rwgt section:

$ lhefilter --max-events 1  pwgevents-0001.lhe  | lhe2lhe --weight-format "rwgt" --append-lhe-weight default default default | lhe2lhe --weight-format "init-rwgt"
<LesHouchesEvents version="3.0">
<init>
   2212   2212  4.0000000e+03  4.0000000e+03    -1    -1    -1    -1    -4     1
 1.3255800e+01  5.9743900e-01  1.0000000e+00  10001
<initrwgt>
  <weightgroup name="default">
    <weight id="default">default</weight>
  </weightgroup>
</initrwgt>
</init>
<event>
  5  10001  1.9892700000e+01  1.9026000000e+01 -1.0000000000e+00  1.6423900000e-01
   21  -1   0   0 501 502  0.00000000e+00  0.00000000e+00  9.59159976e+01  9.59159976e+01  0.00000000e+00  0.0000e+00  9.0000e+00
   -3  -1   0   0   0 511  0.00000000e+00  0.00000000e+00 -2.72494064e+02  2.72494064e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   25   1   1   2   0   0  4.09599828e+01  7.10971103e+00  4.31925771e+01  1.38634178e+02  1.25002274e+02  0.0000e+00  9.0000e+00
   -3   1   1   2   0 502 -3.20825130e+01  1.03220177e+01 -1.96527493e+02  1.99396307e+02  0.00000000e+00  0.0000e+00  9.0000e+00
   21   1   1   2 501 511 -8.87746976e+00 -1.74317287e+01 -2.32431503e+01  3.03795766e+01  4.76837158e-07  0.0000e+00  9.0000e+00
<weights>
 1.9893e+01
</weights>
</event>
</LesHouchesEvents>

Parallelization

Python is slow, but when using all available CPU core the IO speed can become the bottleneck too. To parallelize use GNU parallel:

$ parallel -j 8 lhefix ::: *.lhe

To pick a specific weight ID

$ parallel 'lhe2lhe --only-weight-id aMiNLO -i {} -o {}.aminlo.lhe.gz' ::: fixed_*-rwgt.lhe