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How to ignore a property in class if null, using json.net
...ng property which you can set to ignore.
Here's a sample:
JsonSerializer _jsonWriter = new JsonSerializer {
NullValueHandling = NullValueHandling.Ignore
};
Alternatively, as suggested by @amit
JsonConvert.SerializeObject(myObject, ...
Relative frequencies / proportions with dplyr
...
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vigne...
Swift: Pass array by reference?
...For Swift versions 3-4 (XCode 8-9), use
var arr = [1, 2, 3]
func addItem(_ localArr: inout [Int]) {
localArr.append(4)
}
addItem(&arr)
print(arr)
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SSL Error: CERT_UNTRUSTED while using npm command
...hat running sudo npm cache clean -f then sudo npm install -g n gives a CERT_UNTRUSTED error after the second command.
– fuzzi
Apr 11 '18 at 20:17
2
...
Find and Replace text in the entire table using a MySQL query
...
For a single table update
UPDATE `table_name`
SET `field_name` = replace(same_field_name, 'unwanted_text', 'wanted_text')
From multiple tables-
If you want to edit from all tables, best way is to take the dump and then find/replace and upload it back.
...
Graphviz: How to go from .dot to a graph?
...
1. Install Graphviz from graphviz.gitlab.io/_pages/Download/Download_windows.html 2. Add 'C:\Program Files (x86)\Graphviz2.38\bin' to your system variable PATH 3. Open cmd and go to the dir where you saved the .dot file 4. Use the command 'dot yourFile.dot -Tpng -o i...
Why does cURL return error “(23) Failed writing body”?
...
From the docs: CURLE_WRITE_ERROR (23) An error occurred when writing received data to a local file, or an error was returned to libcurl from a write callback. curl.haxx.se/libcurl/c/libcurl-errors.html
– Jordan Stewart
...
Center image in div horizontally [duplicate]
I have an img in a div ( class="top_image" ) and I want this image to be exactly in the middle of the div but nothing I try works...
...
How to update npm
...get autoremove
sudo apt-get clean
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
sudo apt-get install nodejs
Then :
curl https://raw.githubusercontent.com/creationix/nvm/v0.33.2/install.sh | sh
After this, open a new terminal and check the npm version:
npm --version
EDIT / UP...
Could not load file or assembly or one of its dependencies
...work with Community editions of Visual Studio
– Draex_
Sep 8 '17 at 18:29
I believe there should be another issue, not...