lheutils v0.0.8

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

Rivet

Rivet can read LHE files via HepMC3 to pipe a subset of a LHEFile to Rivet we can use /dev/stdin as source of a piped stream:

lhefilter --events 1,100 filtered2.lhe |  /usr/bin/rivet -a MC_FSPARTICLES /dev/stdin  --verbose

Metadata

Release files for lheutils 0.0.8

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Source distribution for lheutils 0.0.8
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