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Warning message: In `…` : invalid factor level, NA generated
...of 2 variables:
$ Type : Factor w/ 1 level "": NA 1 1
$ Amount: chr "100" "0" "0"
>
> fixed <- data.frame("Type" = character(3), "Amount" = numeric(3),stringsAsFactors=FALSE)
> fixed[1, ] <- c("lunch", 100)
> str(fixed)
'data.frame': 3 obs. of 2 variables:
$ Type : chr ...
What does 'synchronized' mean?
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edited Mar 30 '18 at 7:18
Paolo Forgia
5,49477 gold badges3434 silver badges5555 bronze badges
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Coalesce function for PHP?
...sce function (returns the first non-NULL value, example ). PHP, sadly in 2009, does not.
9 Answers
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Compare given date with today
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290
strtotime($var);
Turns it into a time value
time() - strtotime($var);
Gives you the seconds...
Pass column name in data.table using variable [duplicate]
...list(x, v))
DT[ , eval(temp)]
# x v
# 1: b 1.52566586
# 2: b 0.66057253
# 3: b -1.29654641
# 4: a -1.71998260
# 5: a 0.03159933
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Animate a custom Dialog
...lf-explanatory. This should be located in res/values.
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="PauseDialog" parent="@android:style/Theme.Dialog">
<item name="android:windowAnimationStyle">@style/PauseDialogAnimation</item>
</st...
What is the difference between PS1 and PROMPT_COMMAND
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answered Jun 17 '10 at 1:38
Scott ThomsonScott Thomson
73966 silver badges44 bronze badges
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How to automatically reload a page after a given period of inactivity
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function refresh() {
if(new Date().getTime() - time >= 60000)
window.location.reload(true);
else
setTimeout(refresh, 10000);
}
setTimeout(refresh, 10000);
</script>
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Make a div into a link
...ly the following CSS to the empty span:
{
position:absolute;
width:100%;
height:100%;
top:0;
left: 0;
z-index: 1;
/* fixes overlap error in IE7/8,
make sure you have an empty gif */
background-image: url('empty.gif');
}
It will now cover the panel, and as it's inside ...