Cannot extract item from a list in cmake [duplicate] - list

This question already has an answer here:
Cmake list-get command
(1 answer)
Closed 3 years ago.
I cannot extract an item from a list. The following code replicates my issue:
set(TEST_LIST "aaa" "bbb" "ccc")
list(GET ${TEST_LIST} 1 TEST_ITEM)
message("TEST_ITEM = ${TEST_ITEM}") # Expect: bbb
What I get is:
TEST_ITEM = NOTFOUND
The index 1 should point to the second element bbb. What am I doing wrong?

It works without braces and dollars:
list(GET TEST_LIST 1 TEST_ITEM)

Related

How to query in Mongo for a String based on expressions [duplicate]

This question already has answers here:
Matching a Forward Slash with a regex
(9 answers)
Closed 3 years ago.
I have lot of Data in Mongo DB, I wanted to query based on a String value and that value contains a url
"url" : "http://some-host/api/name/service/list/1234/xyz"
I got records count when executed the below query
db.mycollection.find({url:"http://some-host/api/name/service/list/1234/xyz"}).count()
I want to get all the records which match with
some-host/api/name/service/list/
I tried using below saamples
db.mycollection.find({url:"some-host/api/name/service/list/"}).count()
Got zero records
db.mycollection.find({url:/.*"some-host/api/name/service/list/".*/}).count()
Got error
db.mycollection.find({"url":/.*"some-host/api/name/service/list/".*/}).count()
Got error
db.mycollection.find({"url":/.*some-host/api/name/service/list/.*/}).count()
Got Error
db.mycollection.find({"url":/.*some-host//api//name//service//list//.*/}).count()
Got ...
...
Then no response
Did you try with something like this:
db.mycollection.find({'url': {'$regex': 'sometext'}})
Please check also here

Invalid character in name error Fortran 77 [duplicate]

This question already has answers here:
Type * error in gfortran
(1 answer)
"d" label in the first column, Fortran 77
(1 answer)
Closed 4 years ago.
[enter image description here][enter image description here]1Here is my code below:
BZANGL=BZRANG(IM)
D TYPE *, 'BZANGL=',BZANGL
BANGLE=BZANGL/RDN
Here is my error. Can someone help my understand?
MIAHCODE.f:51:21:
D TYPE * , 'BZANGL=',BZANGL !the D is for -xl[d] debug fortran77
1
Error: Invalid character in name at (1)
As chw21 mentioned, the word 'TYPE' is not a fortran statement. To print the values you desire you can use 'PRINT' or 'WRITE'. Also, as mentioned in the comment above, a D in column 1 signifies nothing. A C in column 1 means the line is a comment.

Why is this '_' used in the third line? Python2.7 [duplicate]

This question already has answers here:
What is the purpose of the single underscore "_" variable in Python?
(5 answers)
Closed 6 years ago.
I am using python to learn about data science. Everything is fine but recently I found below code in a book. I can't understand for what purpose '_' is being used.
def raw_majority_vote(labels):
votes = Counter(labels)
winner, _ = votes.most_common(1)[0]
return winner
In this piece of code you posted, the _ is a variable name.
You can assign values to _.
I.e.:
>>> _ = "test"
>>> print _
Output:
test
If you take a look at Counter.most_common() docs, you'll see this message:
Return a list of the n most common elements and their counts from the
most common to the least. If n is omitted or None, most_common()
returns all elements in the counter. Elements with equal counts are
ordered arbitrarily:
>>> Counter('abracadabra').most_common(3)
[('a', 5), ('r', 2), ('b', 2)]
So, in your code, winner, _ = votes.most_common(1)[0]
The variable winner gets the first value of the first tuple contained in this most_common list.
And the variable, _, gets the second value of the first tuple in this list.
In this case:
winner = 'a'
_ = 5
It's a throwaway variable. Whatever votes.most_common(1)[0] is can be unpacked to two values and the writer of that script is only interested in the first value.
Usually it is used when you don't care about returned variable and you want to discard it but still prevent any ValueErrors.

Get listitem with shortest length from a python list [duplicate]

This question already has answers here:
Python - printing multiple shortest and longest words from a list
(6 answers)
Closed 6 years ago.
I have a orginal list with three words: 'hello', 'hi' and 'Good day'.
I want to create a new_list containing the item with the shortest length. How do I write that code? I use Python 2.7.
original_list=['hello','hi','Good day']
Word Length
'Hello' 5
'Hi' 2
'Good day' 8
Expected output (since I only want the item with the shortest length):
new_list=['Hi']
min() takes a key function as an argument, use len as a key function:
>>> original_list = ['hello','hi','Good day']
>>> new_list = [min(original_list, key=len)]
>>> new_list
['hi']
This though does not handle multiple items with the same shortest length - e.g. ['hello','hi','Good day', 'me'] input list.

Mongo reverse regex [duplicate]

This question already has answers here:
MongoDB reverse regex
(2 answers)
Closed 8 years ago.
In SQL it is possible to run a query similar to
SELECT result FROM table WHERE 'abc-def-ghi' LIKE col1
on a table like this:
col1 | result
abc-% | 1
abc-d% | 2
as% | 3
... | ...
and get a result set with 1 and 2.
Problem: how do I achieve same effect in mongodb?
I can run regex to match against fields but is there a way that the fields could be match agains supplied data?
You can use the $where operator, e.g.:
db.col.find({$where: "\"abc\".match(this.col1)"})
Although MongoDB documentation doesn't recommend using $where, it is the only possibility as far as I know.
(This question is probably a duplicate. See MongoDB reverse regex)
db.stuff.find( { col1 : /supplied_data/ }, { result : 1 } );
Will return only the result field.