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ValueError: math domain error
...gt;>> log(-1)
Traceback (most recent call last):
File "<pyshell#59>", line 1, in <module>
log(-1)
ValueError: math domain error
Without knowing what your newtonRaphson2 function does, I'm not sure I can guess where the invalid x[2] value is coming from, but hopefully this w...
How to toggle a value in Python
...rom the total is a simple and fast way to toggle values:
>>> A = 5
>>> B = 3
>>> total = A + B
>>> x = A
>>> x = total - x # toggle
>>> x
3
>>> x = total - x # toggle
>>> x
5
>>> x = total - x # toggle
>>...
How to create a video from images with FFmpeg?
... the fps video filter instead of -r for the output framerate
ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
Alternatively the format video filter can be added to the filter chain to replace -pix_fmt yuv420p like "fps=25,format=yuv420p". The advantage of this met...
Scaling Node.js
...c 1/4/1.082
SET: 20000 ops 41237.11 ops/sec 0/6/1.210
GET: 20000 ops 39682.54 ops/sec 1/7/1.257
INCR: 20000 ops 40080.16 ops/sec 0/8/1.242
LPUSH: 20000 ops 41152.26 ops/sec 0/3/1.212
LRANGE (10 elements): 20000 ops 36563.07 ops/sec 1/8/1.363
LRANGE (100 elements): 20000 ops 21834.06 ops/sec 0/9/2.28...
Fastest way to replace NAs in a large data.table
...le) # v1.6.6
require(gdata) # v2.8.2
set.seed(1)
dt1 = create_dt(2e5, 200, 0.1)
dim(dt1)
[1] 200000 200 # more columns than Ramnath's answer which had 5 not 200
f_andrie = function(dt) remove_na(dt)
f_gdata = function(dt, un = 0) gdata::NAToUnknown(dt, un)
f_dowle = function(dt) { ...
Python: Get the first character of the first string in a list?
...
answered Aug 18 '11 at 13:25
agfagf
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...
Convert list of dictionaries to a pandas DataFrame
... edited Jul 22 at 17:24
cs95
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answered Dec 17 '13 at 15:35
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