16,359 questions
1
vote
1
answer
83
views
Rules of Unbounded type parameters in Generics ( C# )
I am unable to understand below points about unbounded type parameters.
Type parameters that have no constraints, such as T in public class
SampleClass{}, are called unbounded type parameters.
...
- 95
0
votes
1
answer
250
views
Google Sheets: how to use is not null in a query of another sheet but referencing a cell in the formula sheet
I am trying to get data from another sheet using the content of a cell where I have the formula but I need to avoid blank or 0s in that cell.
Here is my formula:
=query(dataset!$D$3:$T$5004 , "...
2
votes
1
answer
113
views
Why is concatenation called when using dynamic obj + class obj?
I have such an example code:
static void Main()
{
dynamic dynamicObject = null;
object simpleObject = dynamicObject + new AnyClass();
Console.WriteLine(simpleObject);
}
class AnyClass
{
...
- 59
0
votes
0
answers
32
views
Property of custom JPanel is null during repaint but present during Timer execution
This one has me and Gemini both stumped.
The property of Drawing.sceneRootNode evaluates to null or the instance I set depending on whether it's being seen from paint operation or from swing timer ...
user8112809
0
votes
1
answer
66
views
vector does not get appended and is NULL. Why?
I don't know why, but the vector is NULL after running the function. I have checked manually that the if-condition is true for at least some rows of my data frame. If I rund the if statement for i=84, ...
- 19
0
votes
3
answers
164
views
Compare two String in Java with possible null/empty values, when one is null and another is empty it will return true
Looking for a way (OK with using Apache libs as well), to compare two String in Java with possible null/empty values, where the main requirement is when if one is null and another is empty ("&...
- 15.6k
0
votes
1
answer
123
views
Impute missing values in a Pandas dataframe column depending of the most frequent value grouped by a different column
I'm trying to impute the missing values in the column A with the most frequent value of the same column, but depending on how it is grouped with the column B.
Let em explain better:
This is part of my ...
- 3
0
votes
1
answer
49
views
Can't equate one column in an Access record with another column in the same record
I am working with Access version MS 365 Apps for enterprise (desktop version).
When I try to get a specific field value out of my table, I instead get the equivalent to an empty or null result.
I'm in ...
- 1
3
votes
1
answer
181
views
Check for null value and still get a warning
I can't understand why in this code I get a warning (CS8604) on the statement value.ToString() at the last line. It's often that i check for null value and still get a warning.
foreach (Cell c in ...
- 354
0
votes
1
answer
139
views
{ "title": "Validation error", "message": "notNull Violation: User.firstName cannot be null,\nnotNull Violation: User.lastName cannot be null",
im getting the following error when I try to signup for a new user for my RestAPI using postman:
{
"title": "Validation error",
"message": "notNull Violation: User....
- 1
0
votes
1
answer
110
views
how to get null when allocating memory with malloc
Body:
I am working on a C codebase, and I need to write a test case to handle the scenario where malloc returns NULL in the s21_create_matrix function. Below is the relevant portion of the code:
int ...
- 1
0
votes
1
answer
139
views
Importing Complex Pandas Dataframe into Oracle Table
I have a CSV of 74 fields of mix types including dates and 10 rows with data in some columns but not most. The CSV non-data cells are empty (no nan, NULL, or coded values for missing). I'm trying to ...
- 11
0
votes
1
answer
80
views
Including NULL entries in for loop
I'm pulling values into a new dataframe. The values come from an object with columns that contain lists and I need to pull specific values from specific columns/lists for each row. I've created a for ...
- 13
0
votes
2
answers
1k
views
C# - How can I check if a field exists before trying to query it in a JSON JToken?
I am pulling down JSON data from a website and some of the fields are optional, meaning they do not always exist. When I try to query them, my program breaks. I believe I am checking for nulls ...
- 724
2
votes
1
answer
178
views
How to tell if a variable was passed in PowerShell
function turtlesong {
param(
[string]$time,
[string]$link,
[string]$number
)
# create exception for when variables are not passed
if ($time -eq $null -or $link -...
- 23
0
votes
0
answers
96
views
How to check whether an iterator is uninitialized in C++? or compare an iterator against NULL?
I was implementing LRU Cache in C++.
Here is what the class looks like,
class LRUCache {
private:
int capacity;
list<pair<int,int>> memory; // key,value
...
- 1
-1
votes
1
answer
129
views
Finding non null value using single line of code c#
I'm trying to find non null value from 3 strings using a single line code with some null checks in place.I'm getting NULL reference errors here as the c# is checking both sides of the "if" ...
- 799
-2
votes
1
answer
75
views
Can not iterate over null error at stdin 18
Scanning linux images...
Running kernel seems to be up-to-date.
No services need to be restarted.
No containers need to be restarted.
No user sessions are running outdated binaries.
No VM guests are ...
0
votes
2
answers
176
views
Is casting a null pointer to a reference defined behavior?
I have this piece of C++ code:
int main() {
int* ptr = nullptr;
int& ref = reinterpret_cast<int&>(ptr);
return ref;
}
While compiling with -Wall -Wextra -pedantic on both ...
- 329
-3
votes
1
answer
70
views
problems with null and empty string array
class ToDoList {
public static void toDO() {
List<string[]> addEntry = [];
bool toDoLoop = true;
while (toDoLoop) {
Clear();
WriteLine(&...
user23195977
0
votes
1
answer
137
views
How can I properly save/convert or read Color to JSON?
I want to change the color of the background of my text field using a color picker. (I used flutter_colorpicker)
create_journal.dart
late Color _selectedBackgroundColor;
void initState() {
super....
3
votes
4
answers
221
views
NULL-input for concatenated string in generated column
I have a table
CREATE TABLE IF NOT EXISTS club.climbers
(
climber_id SERIAL PRIMARY KEY,
climber_first_name VARCHAR(20) NOT NULL,
climber_last_name VARCHAR(30) NOT NULL,
...
- 33
0
votes
2
answers
724
views
I want to write out "NULL" values from 1 column into an excel file from a DataFrame
I have multiple excel files. I import the data into 1 DataFrame in Python. Then I sort the information by an Index field, and afterwards I want to export the Dataframe into an excel file.
All goes ...
- 3
0
votes
1
answer
44
views
How do I use .fillna to fill based on a list of mean values that are grouped by another column? [duplicate]
I have a dataframe named df that has null values for Bandwidth_GB_Year.
I am trying to fill the null values based on the means that are grouped by another column, InternetService.
When I use fillna, ...
0
votes
2
answers
107
views
PHP APİ CURL Get Null
$curl = curl_init();
curl_setopt_array($curl , [
CURLOPT_RETURNTRANSFER =>TRUE,
CURLOPT_URL => 'https://ortam.etu.edu.tr/Services/get_user_card_information/?apikey=XXXXXXXXX&...
user17376014