Im using pow from cmath.h for the power of function. Im using the line of code pow(80,7). Int and long are to small to give me the right value. Im going to use printf or cout to display the result
what data type can I use
Maybe you should have a look at GNU GMP (https://gmplib.org/).
HTH!
Related
I see requests to socket.io containing parameter t to be like LZywzeV, LZz5lk7 and similar.
All examples that i found so far used second- or millisecond-based UNIX timestamps.
Has anyone ever seen a timestamp format like this? (It is not base64-encoded).
I started looking a site that uses Socket.io today, and got the same problem, trying to look for the protocol definition was useless.
I figured this format is something called yeast
TBH, really don't know why people invent this sort of things instead of use
base64(timestamp.getBytes())
pseudocode instead.
A yeast decode algorithm in Python is as follow:
from datetime import datetime
a='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_'
b={a[i]: i for i in range(len(a))}
c=0
for d in "LZywzeV":
c=c*64+b[d]
print(c)
print(datetime.fromtimestamp(c/1000))
The output of that code is:
1481712065055
2016-12-14 07:41:05
to #jeremoquai:
It is easy, is matter of invert the algorithm:
def yeast(d):
r=""
while d!=0:
r='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_'[d&63]+r
d>>=6
return r
so, if you run
yeast(1481712065055)
it returns LZywzeV
I am trying to create a data field using Mockaroo and they say they have Ruby support but I know nothing about Ruby so I am trying to find out how to do a field that will randomly choose between the 3 options.
now() or
now()+days(-1) or
now()+days(-2) or
now()+days(-3)
Idea 1
I was initially thinking something using random like now()+days(this.rand(-3))
Idea 2
I also thought of using or logic like now() or now()+days(-3) or etc...
This answer may end up being different than a typical ruby solution since Mockaroo has their own little API to use too... Appreciate any help that can be given.
Turns out I had to use the random function first and pass in min and max date parameters.
random(now()+days(2), now()+days(-3))
I am trying to get a set of binary images' eccentricity and solidity values using the regionprops function. I obtain the label matrix using the vision.ConnectedComponentLabeler function.
This is the code I have so far:
files = getFiles('images');
ecc = zeros(length(files)); %eccentricity values
sol = zeros(length(files)); %solidity values
ccl = vision.ConnectedComponentLabeler;
for i=1:length(files)
I = imread(files{i});
[L NUM] = step(ccl, I);
for j=1:NUM
L = changem(L==j, 1, j); %*
end
stats = regionprops(L, 'all');
ecc(i) = stats.Eccentricity;
sol(i) = stats.Solidity;
end
However, when I run this, I get an error says indicating the line marked with *:
Error using ConnectedComponentLabeler/step
Variable-size input signals are not supported when the OutputDataType property is set to 'Automatic'.'
I do not understand what MATLAB is talking about and I do not have any idea about how to get rid of it.
Edit
I have returned back to bwlabel function and have no problems now.
The error is a bit hard to understand, but I can explain what exactly it means. When you use the CVST Connected Components Labeller, it assumes that all of your images that you're going to use with the function are all the same size. That error happens because it looks like the images aren't... hence the notion about "Variable-size input signals".
The "Automatic" property means that the output data type of the images are automatic, meaning that you don't have to worry about whether the data type of the output is uint8, uint16, etc. If you want to remove this error, you need to manually set the output data type of the images produced by this labeller, or the OutputDataType property to be static. Hopefully, the images in the directory you're reading are all the same data type, so override this field to be a data type that this function accepts. The available types are uint8, uint16 and uint32. Therefore, assuming your images were uint8 for example, do this before you run your loop:
ccl = vision.ConnectedComponentLabeler;
ccl.OutputDataType = 'uint8';
Now run your code, and it should work. Bear in mind that the input needs to be logical for this to have any meaningful output.
Minor comment
Why are you using the CVST Connected Component Labeller when the Image Processing Toolbox bwlabel function works exactly the same way? As you are using regionprops, you have access to the Image Processing Toolbox, so this should be available to you. It's much simpler to use and requires no setup: http://www.mathworks.com/help/images/ref/bwlabel.html
I have a blob in postgresql database. Have inserted a C structure into it.
struct temp {
uint64_t a,
uint64_t b,
uint64_t c
};
Now when I write q query in shell for retrieving it.
select resource,.....,blob_column from rtable where rId is=1
I got the result as a blob from database. the result is
x00911ee3561ac801cb0783462586cf01af00000000000000
But now in shell script I need to iterate on this and display the result on console. Tried different things like awe,split , convert_from ,convert function but nothing is helping me.
Can someone tell me how can I read this hex string and get back the integers?
Is this some kind of exersise in programmer-torture? I can't imagine why you'd possibly do this. Not least because your struct-as-a-blob could be subject to padding and alignment that will vary from compiler to compiler and platform to platform. Even then, it'll vary between architectures because of endianness differences. At least you used fixed-width types.
Assuming you only care about little-endian and your compilers don't add any padding or alignment (likely for a struct that's just 3 64-bit fields) it's possible. That doesn't make a great idea.
My preferred approach would be to use some Python code with struct, e.g.
python - "x00911ee3561ac801cb0783462586cf01af00000000000000" <<__END__
import sys
import struct
print "{} {} {}".format(*struct.unpack('#QQQ', sys.argv[1][1:].decode("hex")))
__END__
as this can even handle endianness and packing using appropriate modifiers, and you can easily consume the output in a shell script.
If that's not convenient/suitable, it's also possible in bash, just absolutely horrible. For little-endian, unpadded/packed-unaligned:
To decode each value (adapted from https://stackoverflow.com/a/3678208/398670):
$ x=00911ee3561ac801
$ echo $(( 16#${x:14:2}${x:12:2}${x:10:2}${x:8:2}${x:6:2}${x:4:2}${x:2:2}${x:0:2} ))
so, for the full deal:
x=x00911ee3561ac801cb0783462586cf01af00000000000000
uint64_dec() {
echo $(( 16#${1:14:2}${1:12:2}${1:10:2}${1:8:2}${1:6:2}${1:4:2}${1:2:2}${1:0:2} ))
}
uint64_dec ${x:1:16}
uint64_dec ${x:17:16}
uint64_dec ${x:33:16}
produces:
128381549860000000
130470408871937995
175
Now, I feel dirty and need to go wash. I strongly suggest the following:
CREATE TYPE my_struct AS (a numeric, b numeric, c numeric);
then using my_struct instead of a bytea field. Or just use three numeric columns. You can't use bigint because Pg doesn't have a 64-bit unsigned integer.
Excel AddIn using Excel DNA, VS2008, C#,
MyUDF(param1, parm2)
when I type in "=MyUDF" and hit enter, Excel displays a huge number like 970063926
and my c# code for MyUDF is not run
Anyone know what is this huge number?
thanks
This is just a bit of weird behaviour of Excel. The number being returned is an internal identifier for the UDF function, and by entering the function name without any brackets, you're causing it to be treated like a named range not a function. If you want to call the function with no arguments, use:
=MyUDF()
...if you type =MyUDF then you're asking Excel to dereference the function name, in the same way that it would dereference =A1 to the value in cell A1 or =MyNamedRange to whatever that named range referred to.
I don't think there's any practical use for the behaviour you've observed, but it certainly isn't going anywhere near your code to get this value that is being returned, so don't worry you haven't done anything wrong!
Is there any way to avoid this behavior?
If no parameter is specified, I would like the =MyUDF to return error instead a number.