How can I automate the execution of a series of functions (with the names “test_1”, “test_2“, … “test_100”) using metaprogramming in DolphinDB?
For example:
def test_2(){
return 1
}
eval(<test_2()>)//output: 1
I want to use a loop to generate the function names as strings and pass them to eval for execution. But when I passed the function name as a string to eval, the result is not what I wanted:
eval(<'test_2()'>)//output: test_2()
You can use parseExpr() to convert the string “test_2()“ into metacode (<test_2()>), then execute it with eval(). To automate the execution of all 100 functions, simply write a loop that generates strings of the function names.
Alternatively, you can also use functionByName to dynamically execute a function. In your example:
loop(x->funcByName("test_" + string(x))(), 1..100)
For more information about functionByName, see the DolphinDB official documentation.
Related
I have, in a database, records that are serialized PHP strings that I must obfuscate emails if there are any. The simplest record is like {s:20:"pika.chu#pokemon.com"}. It is basically saying: this is a string of length 20 which is pika.chu#pokemon.com. This field can be kilobytes long with lot of emails (or none) and sometimes it is empty.
I wish I could use a SQL regular expression function to obfuscate the user part of the email while preserving the length of the string in order not to break the PHP serialization. The example email above shall be turned into {s:20:"xxxxxxxx#pokemon.com"} where the number of x matches the length of pika.chu.
Any thoughts?
Here is a more complete example of what can be found as serialized PHP:
a:4:{s:7:"locales";a:3:{i:0;s:5:"fr_FR";i:1;s:5:"de_DE";i:2;s:5:"en_US";}s:9:"publisher";s:18:"john#something.com";s:7:"authors";a:2:{i:0;s:21:"william#something.com";i:1;s:19:"debbie#software.org";}s:12:"published_at";O:8:"DateTime":3:{s:4:"date";s:26:"2022-01-26 13:05:26.531289";s:13:"timezone_type";i:3;s:8:"timezone";s:3:"UTC";}}
I tried to do it using native functions but it not worked because functions like REGEXP_REPLACE don't let you manipulate the match to get the size of it, for example.
Instead, I've created a UDF to do that:
CREATE TEMP FUNCTION hideEmail(str STRING)
RETURNS STRING
LANGUAGE js AS """
return str
.replace(/([a-zA-Z.0-9_\\+-:]*)#/g, function(txt){return '*'.repeat(txt.length-1)+"#";})
""";
select hideEmail('a:4:{s:7:"locales";a:3:{i:0;s:5:"fr_FR";i:1;s:5:"de_DE";i:2;s:5:"en_US";}s:9:"publisher";s:18:"john#something.com";s:7:"authors";a:2:{i:0;s:21:"william#something.com";i:1;s:19:"debbie#software.org";}s:12:"published_at";O:8:"DateTime":3:{s:4:"date";s:26:"2022-01-26 13:05:26.531289";s:13:"timezone_type";i:3;s:8:"timezone";s:3:"UTC";}}')
Result:
a:4:{s:7:"locales";a:3:{i:0;s:5:"fr_FR";i:1;s:5:"de_DE";i:2;s:5:"en_US";}s:9:"publisher";s:18:"****#something.com";s:7:"authors";a:2:{i:0;s:21:"*******#something.com";i:1;s:19:"******#software.org";}s:12:"published_at";O:8:"DateTime":3:{s:4:"date";s:26:"2022-01-26 13:05:26.531289";s:13:"timezone_type";i:3;s:8:"timezone";s:3:"UTC";}}
I need to execute a SQL query, which converts a String column to a Array and then validate the size of that array
I was able to do it easily with postgresql:
e.g.
select
cardinality(string_to_array('a$b','$')),
cardinality(string_to_array('a$b$','$')),
cardinality(string_to_array('a$b$$$$$','$')),
But for some reason trying to convert String on vertica to array is not that simple, Saw this links:
https://www.vertica.com/blog/vertica-quick-tip-dynamically-split-string/
https://forum.vertica.com/discussion/239031/how-to-create-an-array-in-vertica
And much more that non of them helped.
I also tried using:
select REGEXP_COUNT('a$b$$$$$','$')
But i get an incorrect value - 1.
How can i Convert String to array on Vertica and gets his Length ?
$ has a special meaning in a regular expression. It represents the end of the string.
Try escaping it:
select REGEXP_COUNT('a$b$$$$$', '[$]')
You could create a UDx scalar function (UDSF) in Java, C++, R or Python. The input would be a string and the output would be an integer. https://www.vertica.com/docs/9.2.x/HTML/Content/Authoring/ExtendingVertica/UDx/ScalarFunctions/ScalarFunctions.htm
This will allow you to use language specific array logic on the strings passed in. For example in python, you could include this logic:
input_list = input.split("$")
filtered_input_list = list(filter(None, input_list))
list_count = len(filtered_input_list)
These examples are a good starting point for writing UDx's for Vertica. https://github.com/vertica/UDx-Examples
I wasn't able to convert to an array - but Im able to get the length of the values
What i do is convert to Rows an use count - its not best performance wise
But with this way Im able to do also manipulation like filtering of each value between delimiter - and i dont need to use [] for characters like $
select (select count(1)
from (select StringTokenizerDelim('a$b$c','$') over ()) t)
Return 3
function y = objfun(x)
sim('modelprototype.slx');
y = Y(1);
end
It is in simulink embedded func block.
Before that I ask for help, I will explain what I did and what I want;
I had a function as a script in matlab. Having entered the parameters to fmincon to optimize my fuction, It worked correctly. And iterated 9 times and lastly found the minimum value of my function;
But the problem is occured when I decided to write the function in a embedded function existing in simulink model. Like I did above I entered all parameters for fmincon it only iterates 3 times and the values are same. I could not find the minimum value.
Please help me to find a solution to optimize the function in simulink model like that same function written as ascript file in matlab.
I want to write the function indicated in that link in simulink embedded function block and optimize it;
You can find information from the link below;
-https://www.mathworks.com/help/optim/ug/output-functions.html
You can reach Code and File
-https://github.com/saibermehmet/MATLAB.git
I again indicate that I want to optimize the obj function when it is a embedded function block in simulink instead of a ordinary function m-file.
I am using Deep learning Theano. How can I see the content of a variable like this: Elemwise{tanh,no_inplace}.0. It is the input data of logistic layer.
Suppose your variable is called t. Then you can evaluate it by calling t.eval(). This may fail if input data are needed. In that case you need to supply them by providing a dictionary like this t.eval({input_var1: value1, input_var2: value2}). This is the ad-hoc way of evaluating a theano-expression.
The way it works in real programs is to create a function taking the necessary input, for example: f = theano.function([input_var1, input_var2], t), will yield a function that takes two input variables, calculates t from them and outputs the result.
Right now, you don't seem to print values but operations. The output Elemwise{tanh,no_inplace}.0 means, that you have an element wise operation of tanh, that is not done in place. You still need to create a function that takes input and executes your operation. Then you need to call that function and print the result. You can read more about that in the graph-structure part of their tutorial.
I am working in an ABAP program and I have a question.
For example in C# when we have a String variable: string name; , and we want this to be filled with some data from a textbox but also add some ohter text.
For example:
string name = "Hello: " + textBox1.text;,
And I want to ask you how can I do this in ABAP ??? How to add text plus the text written from a Parameter type C?
CONCATENATE and the concatenate operator && will do it as answered by Jagger and vwegert. To do it with string expressions, you use the below where name is the screen field or whatever that has the name in it (it doesn't need to be a field-symbol):
greeting = |Hello: { <name> }|.
String expressions are extremely useful as they can be used to build up complex values without declaring extra variables - e.g. they can passed as directly as function module or method parameters without first assigning to a local variable.
You can either use the CONCATENATE keyword or -- in newer releases -- string expressions. Be sure to check the online documentation and sample programs available using the transaction ABAPDOCU, it will save you a ton of seemingly basic questions.
The equivalent operator is &&.
So in your case it would be:
name = 'Hello: ' && textBox1->text.