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Numeric variables, addition & subtraction
I have a numeric variable, and I’d like to do some addition / subtraction calculations on it to either a) create / update a different variable, or just output the result of the calculation.
Is such a thing possible with native tags, please? I’ve checked docs and not struck gold as yet, but since this is my first ever time using variables with calculations, I may well be missing something fundamental.
Thank you.
Caveat: this might be a job for etc_query, but I figured I’d ask about the native approach.
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Re: Numeric variables, addition & subtraction
<txp:variable name="my_counter" add /> will increment a value by 1. Use add="5" to change the positive step, or negative numbers to subtract values each time the tag is encountered.
Wrap it in another <txp:variable> tag to update a different variable. You can use the output attribute to display/return the current value.
For anything more, plug your variable tags into <txp:evaluate> to do more complex stuff.
The docs are woefully lacking, oops…
Last edited by Bloke (Yesterday 18:17:50)
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Re: Numeric variables, addition & subtraction
Bloke wrote #341062:
The docs are woefully lacking, oops…
My grey matter is somewhat lacking, too…I think a few hours of finagling is in order, and I’ll share the results when (if) they work.
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Re: Numeric variables, addition & subtraction
Actually, I just checked, and there are some good examples on the txp:variable tag doc page that might give you some ideas of usage.
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Re: Numeric variables, addition & subtraction
Against considerable (brain-related) odds, I’ve got a working scaffold for the following conditions:
- Get the current day of the year with PHP; increment by one since years start on day 0 in PHP.
- Block out two time periods of the year: the six months around the shortest day is ‘Dark’, and the six months around the longest day is ‘Light’.
- If the current day is ‘Dark’ find the number of days until ‘Light’, and vice versa.
…and it works! My first use of variable with evaluate has a check in its box.
Leap year stuff is beyond scope for now, but I’ve got some time to figure that out.
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Re: Numeric variables, addition & subtraction
Nice work!
For cleanliness, you should be able to remove the PHP block and use the native <txp:date> tag in 4.9.0.
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Re: Numeric variables, addition & subtraction
Bloke wrote #341066:
For cleanliness, you should be able to remove the PHP block and use the native <txp:date> tag in 4.9.0.
Jackpot. Thank you very much.
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