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How to format numbers by prepending 0 to single-digit numbers?
I want to format a number to have two digits. The problem is caused when 0 – 9 is passed, so I need it to be formatted to 00 – 09 .
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Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data fr...
How to create an array containing 1…N
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409
If I get what you are after, you want an array of numbers 1..n that you can later loop through....
Convert NaN to 0 in javascript
Is there a way to convert NaN values to 0 without an if statement:
11 Answers
11
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Logical operators for boolean indexing in Pandas
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When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x']==1) and (a['y']==10) to boolean values.
NumPy arrays (of length greater than 1) and Pandas objects such as Series do not have a boolean value -- in other words, they ...
Suppress warning CS1998: This async method lacks 'await'
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107
I've got an interface with some async functions.
Methods returning Task, I believe. async ...
Matplotlib tight_layout() doesn't take into account figure suptitle
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10 Answers
10
Active
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Zero-pad digits in string
I need to cast single figures (1 to 9) to (01 to 09). I can think of a way but its big and ugly and cumbersome. I'm sure there must be some concise way. Any Suggestions
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How to automatically generate N “distinct” colors?
...tness or saturation, you can distribute the hues like so:
// assumes hue [0, 360), saturation [0, 100), lightness [0, 100)
for(i = 0; i < 360; i += 360 / num_colors) {
HSLColor c;
c.hue = i;
c.saturation = 90 + randf() * 10;
c.lightness = 50 + randf() * 10;
addColor(c);
}
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Why does ('0' ? 'a' : 'b') behave different than ('0' == true ? 'a' : 'b') [duplicate]
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208
+500
First, ...