SIMPSON like 1D and 2D [.spe]

Simpson 1D ascii files ((read and save download an example

Warning : the coding of the SIMPSON Header previously used combinations of X0, Sr and dX values resulting in redundant coding of the frequency and inconsistent results [marginally in most cases]. From dmfit #20170801 the header has been reduced to X0 only as described below. The compatibility is maintained as much as possible.
Many thanks to Simone Weigelt for mentioning and identifiying this issue.

for a spectrum : TYPE=SPE - taken to be described in decreasing frequency
+ the X0 parameter is the Hz position of the left most point
+ the X increment is taken as dX = -SW/NP
+ the SF value is the reference frequency for computing ppm scale and NMR interactions

example of SIMPSON header :
SIMP
Comment= Saved by dmfit #20170801
NP=2048
X0=12237.3
SW=20000
Sf=50.3292
TYPE=SPE of FID
DATA
re im
...
n times
...

for a 2D spectrum X0_F1 and SF1 are added to the SW1 parameter in the same wayy