Counters

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< Main Page | Inside ConTeXt >

ConTeXt provides a higher layer of API to access various counters. For example, to set the page number to a certain value use \setcounter:

 \setcounter[userpage][1]

Other useful commands for working with counters are

Names of Commonly Used Counters

  • userpage for visible pagenumbers
  • page for internal pagenumbers
  • formula for formula numbers
  • table for table numbers
  • figure for figure numbers


Testing the Value of a Counter

If you need to test the value of a counter, use \rawcountervalue, not \getcounter:

\definecounter[mynumber][]
\setcounter[mynumber][42]
\doifelse{\getcounter[mynumber]}{42}{
 Strange, \type{\getcounter} worked.
}{
 Using \type{\getcounter} does not work.
}

\doifelse{\rawcountervalue[mynumber]}{42}{
 Ok, the test with \type{\rawcountervalue} worked.
}{
 Strange, \type{\rawcountervalue} failed.
}

results in:

In LMTX, \getcounter seems to be generally defunct.

Coupling Counters

Two counters can be coupled by

 \definecounter[one]
 \definecounter[two][one]

For example

\definecounter[one]
\definecounter[two][one]


Default value of counter one: \rawcountervalue[one]

We increment counter two
\incrementcounter[two]

New value of counter one: \rawcountervalue[one]

By default counters are reset with each new chapter. To have a counter which isn’t reset you need way=bytext, and to remove the chapter number from the \getcounter result you have to add prefix=no.

Example definition:

\definecounter[examplecounter][way=bytext,prefix=no]

Outdated information

Forcing the Reset of a Counter

In 2015, there was a bug that counters were reset (by chapter, page, etc.) only when they were incremented.

To force the reset, you can increment and then decrement a counter before using it.

\definecounter[mycounter][way=bypage]
\setcounter[mycounter][10]
\rawcountervalue[mycounter]
\page                       % new page, mycounter should be reset
\rawcountervalue[mycounter] % no, it's not reset: you still get '10'

\incrementcounter[mycounter]\decrementcounter[mycounter]
\rawcountervalue[mycounter] % now you should get '0' because it has been reset

\definenumber or \definecounter ?

\definenumber etc. are obsolete aliases for \definecounter etc.