setkey sorts a data.table and marks it as sorted with an attribute sorted. The sorted columns are the key. The key can be any number of columns.
What does setkey (...) do?
This has some practical implications: for one thing if you set the key in a table with setkey(...)and then change any of the values in the key column, data.table merely declares the table to be no longer sorted (by turning off the sortedattribute); it does notdynamically re-index to maintain the proper sort order (as would happen in a database).
What is a data set key?
The set keyenables a key (or legend) describing plots on a plot. The contents of the key, i.e., the names given to each plotted data set and function and samples of the lines and/or symbols used to represent them, are determined by the titleand withoptions of the {s}plotcommand. Please see plot title (p. )and plot with (p. )for more information.
What is a set key in a plot?
The set keyenables a key (or legend) describing plots on a plot. The contents of the key, i.e., the names given to each plotted data set and function and samples of the lines and/or symbols used to represent them, are determined by the titleand withoptions of the {s}plotcommand. Please see plot title (p.
What is a set key in R?
The set key enables a key (or legend) describing plots on a plot. The contents of the key, i.e., the names given to each plotted data set and function and samples of the lines and/or symbols used to represent them, are determined by the title and with options of the {s}plot command.
What does setkey do?
Description. setkey sorts a data. table and marks it as sorted with an attribute sorted . The sorted columns are the key.
What is a key in R?
Description. Key is a vector which goal is to provide information about rows in reference data frame. Its length should always be equal to number of rows in data frame. Keys are stored as tibble in attribute "keys" and so one data frame can have multiple keys.
What is key chart?
When used in a graph or a map, a key, also referred to as a legend, is the part that explains the symbols used. Most commonly, keys are drawn off to the side of a graph or below it. Usually this involves drawing all the symbols used then indicating what the symbols represent.
What is a figure key?
Key figures are financial calculations that are used to analyse a company's affairs and condition. Your company's reports at your fingertips in just a couple clicks.
What is a loop in R?
In R programming, we require a control structure to run a block of code multiple times. Loops come in the class of the most fundamental and strong programming concepts. A loop is a control statement that allows multiple executions of a statement or a set of statements. The word 'looping' means cycling or iterating.
What is a dictionary in R?
Dict is a R package which implements a key-value dictionary data structure based on R6 class. It is designed to be similar usages with other languages' dictionary implementations (e.g. Python). R's vector and list , of course can have names, so you can get and set value by a name (key) like a dictionary.
What is the operator in R?
An operator is a symbol that tells the compiler to perform specific mathematical or logical manipulations. R language is rich in built-in operators and provides following types of operators.
How do you use Lapply in R?
lapply function in RThe lapply function is part of the apply family functions in R and allows applying a function over a list or a vector, returning a list. ... Using the lapply function is very straightforward, you just need to pass the list or vector and specify the function you want to apply to each of its elements.More items...
What is setkey()?
setkey()sorts a data.tableand marks it as sorted. The sorted columns are the key. The key can be any columns in any order. The columns are sorted in ascending order always. The table is changed by reference. No copy is made at all, other than temporary working memory as large as one column.
When is setkey () required?
For grouping operations, setkey () was never an absolute requirement. That is, we can perform a cold-by or adhoc-by.
What is keying data table?
Keying a data.tablephysically reorders it based on those column(s) in RAM. Computing the order is not usually the time consuming part, rather the reorderingitself. However, once we've the data sorted in RAM, the rows belonging to the same group are all contiguous in RAM, and is therefore very cache efficient. It's the sortedness that speeds up operations on keyed data.tables.
Which operation requires keyto be absolutely set?
The only operation that requires keyto be absolutely set is the foverlaps()function. But we are working on some more features which when done would remove this requirement.
Can a data table have more than one key?
Therefore, a data.table can have at most one key, because it cannot be sorted in more than one way. Uniqueness is not enforced, i.e., duplicate key values are allowed. Since the rows are sorted by the key, any duplicates in the key will appear consecutively. The telephone directory was helpful in understanding what a key is, ...
Is a key different from a factor column?
The telephone directory was helpful in understanding what a key is, but it seems that a key is no different when compared to having a factor column. Furthermore, it does not explain why is a key needed (especially to use certain functions) and how to choose the column to set as key.
What is a security key?
We currently support several designs and providers of security keys using the Fast Identity Online (FIDO2) passwordless authentication protocols. These keys allow you to sign in to your work or school account to access your organization's cloud-based resources when on a supported device and web browser.
How to manage security key?
Open the Windows Settings app, select Accounts, select Sign-in options, select Security Key, and then select Manage.
How to delete all information on a security key?
If you want to delete all the account information stored on your physical security key, you must return the key back to its factory defaults. Resetting your security key deletes everything from the key, allowing you to start over.
What happens if you don't see security key?
If you don't see the security key option, it's possible that your organization doesn't allow you to use this option for verification. In this case, you'll need to choose another method or contact your organization's help desk for more assistance.
Is a security key FIDO2?
You have a physical security key approved by your administrator or your organization. Your security key must be both FIDO2 and Microsoft-compliant. If you have any questions about your security key and whether it's compatible, contact your organization's help desk.
Can you use a security key as a password?
You can use security keys as a passwordless sign-in method within your organization. A security key is a physical device that's used with a unique PIN to sign in to your work or school account. Because security keys require you to have the physical device and something that only you know, it's considered a stronger verification method than a username and password.
What is set object?
Set objects are collections of values. You can iterate through the elements of a set in insertion order. A value in the Set may only occur once; it is unique in the Set 's collection.
What does Set.prototype.has return?
Set.prototype.has (value) will return false afterwards.
Is each entry's key the same as its value for a set?
This is similar to the Map object, so that each entry's key is the same as its value for a Set.
What is the setup key for authenticator?
During authenticator app 2FA setup, you can view the setup key — which is just the QR code in text form. It is sometimes also referred to as a " backup code " or " secret seed code ".
Why is it important to enable a master key?
Enabling a Master Key instead of copying the authenticator setup key is preferable because it can be changed in the event that somebody learns it. The Master Key can also be enabled as a dynamic code that changes with each use (by using an Authenticator App or Yubikey). Was this article helpful?
What is 2FA authentication key?
The 2FA authenticator setup key serves as a backup for your Sign-in 2FA codes in case you lose them (e.g. If you accidentally delete the Authenticator App). It is a static code (it does not change with each use) that should be kept safe and treated as a password. It is provided by default from your authenticator App.
Can an authenticator setup key be stored digitally?
The authenticator setup key should be treated the same way you treat a password and should not be stored digitally! If not securely stored, the setup key can be compromised and used to gain access to your account.
Accessibility keys
The following table contains predefined key combinations for accessibility:
Application keys
The following table contains predefined key combinations for controlling application state:
Shell keys
The following table contains predefined key combinations for general UI control:
Modifier keys
The following table contains predefined key combinations for modifier keys (such as Shift and Ctrl):
Security keys
The following table contains predefined key combinations for OS security:
What is a set in math?
In Maths, sets are a collection of well-defined objects or elements. A set is represented by a capital letter symbol and the number of elements in the finite set is represented as the cardinal number of a set in a curly bracket {…}.
What is an empty set?
Empty Set or Null set: It has no element present in it .Example: A = {} is a null set.
What is the power set of a set A?
Answer: In set theory, the power set of a set A is defined as the set of all subsets of the Set A including the Set itself and the null or empty set.
How many forms of sets can be represented?
Sets can be represented in three forms:
What is a subset of B?
Subsets: A set ‘A’ is said to be a subset of B if each element of A is also an element of B.Example: A= {1,2}, B= {1,2,3,4}, then A ⊆ B
What is smart key security?
SmartKey Security™ allows you to re-key your lock yourself in seconds.
Can you rekey your locks yourself?
SmartKey Security™ features re-key technology, which allows you to re-key your locks yourself in seconds, because we realize the person who has your key today may not be the same person you want to have your key tomorrow.
Overview
What is a security key?
- We currently support several designs and providers of security keys using the Fast Identity Onlin…
Your administrator or your organization will provide you with a security key if they require it for your work or school account. There are different types of security keys you can use, for example a USB key that you plug in to your device or an NFC key that you tap on an NFC reader. You can …
Before you begin
- Before you can register your security key, the following conditions must all be met:
Your administrator has turned on this feature for use within your organization. - You're on a device running the Windows 10 May 2019 Update and using a supported browser.
You have a physical security key approved by your administrator or your organization. Your security key must be both FIDO2 and Microsoft-compliant. If you have any questions about your security key and whether it's compatible, contact your organization's help desk.
Register a security key
- You must create your security key and give it a unique PIN before you can sign in to your work o…
Go to the My Profile page at My Account and sign in if you haven't already done so. - Select Security Info, select Add method, and then select Security key from the Add a method list.
Select Add, and then select the type of security key you have, either USB device or NFC device.
Delete a security key from your security info
- If you lose or no longer want to use a security key, you can delete the key from your security info…
Select the Delete link from the security key to remove. - Select OK from the Delete security key box.
Your security key is deleted and you'll no longer be able to use it to sign in to your work or school account.
Manage your security key settings from Windows Settings
- You can manage your security key settings from the Windows Settings app, including resetting y…
Reset a security key - If you want to delete all the account information stored on your physical security key, you must r…
Important: Resetting your security key deletes everything from the key, resetting it to factory defaults. All data and credentials will be cleared.
Security verification versus password reset authentication
- Security info methods are used for both two-factor security verification and for password reset. However, not all methods can be used for both.
Next steps
- For more information about passwordless verification methods, read the Microsoft’s Azure AD b…
Detailed info about Microsoft-compliant security keys. - Reset your password if you've lost or forgotten it, from the Password reset portal or follow the st…
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