QDP_commands
QDP commands must be inserted at the beginning of a QDP file, as
these commands tell QDP how to read in the data. Any command not
recognized by QDP is passed to PLT. QDP separates command lines from
data lines based on the first non-blank character in the line. If
this character is + - . or a digit then the entire line will be read
as data.
READ
Serr
READ Serr [vlist]
Tell QDP/PLT which vectors have symmetric errors. The command
"READ Serr 1 3 5" will cause vectors 1, 3, and 5 to be read with
symmetric errors and vectors 2 and 4 to be read without. Only one
"READ Serr" command should appear in a QDP file
Example:
READ Serr 1 3 5
1. .1 2. 3. .3 4. 5. .5
would be read as 5 vectors; 1. +/- .1; 2. (no error); 3. +/- .3;
4.(no error); 5. +/- .5. Without the "READ Serr" command, the above
would be read as 8 vectors.
Terr
READ Terr [vlist]
Tell QDP/PLT which vectors have two-sided errors. It takes three
columns to specify a vector with two-sided errors. The first column
is the central value, the second column, which must be positive,
specifies the upper bound, and the third column, which must be negative
or zero, specifies the lower bound.
Example:
READ Serr 1
READ Terr 2
1. .1 2. +.1 -2.
would be read as 1. +/-.1; 2 +.1,-2. Note: In fitting, non-positive
errors are ignored and so, the first error, of two-sided errors,
should be positive.
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