Save numbers after text pattern in a vector

Dear all

I have a text file that looks like these:

#------------------------------------------------------
# Atomistic spin configuration file for vampire v5+
#------------------------------------------------------
# Date: Wed Jul 31 19:19:54 2024
#------------------------------------------------------
Time: 1e-15
Field: 0	0	0
Temperature: 0.05
Magnetisation: -0.999883	0.0152572	-0.000478932
#------------------------------------------------------
Number of spin files: 1
spins-00000000.data
#------------------------------------------------------

I am interested in saving in an array the three numerical values after "Field:". I have tried something like

field_str=regexp(meta_file_read,'(?<=^TField:\s+)(\S+)\s*(\S+)\s*(\S+)','match','lineanchors'); % T

But the cell seems to be empty.

Any ideas?

Answer 1

[Rik]

Having a typo in your needlessly complicated regex doesn't help:

meta_file_read=["#------------------------------------------------------"
"Time: 1e-15"
"Field: 0	0	0"
"Temperature: 0.05"
"Magnetisation: -0.999883	0.0152572	-0.000478932"
"#------------------------------------------------------"];
[field_str,tokens]=regexp(meta_file_read,...
    '^Field:\s+(\S+)\s*(\S+)\s*(\S+)',...
    'match','tokens')

field_str = 6x1 cell array
    {0x0 string        }
    {0x0 string        }
    {["Field: 0->0->0"]}
    {0x0 string        }
    {0x0 string        }
    {0x0 string        }

tokens = 6x1 cell array
    {0x0 string}
    {0x0 string}
    {1x1 cell  }
    {0x0 string}
    {0x0 string}
    {0x0 string}

tokens{3}{1}

ans = 1x3 string array
    "0"    "0"    "0"