iloc method return different type of data
I have a dataset 30 obs and 2 columns i used code below to create independent and depend dataset for a single linear regression.
So each dataset is expected to be a 1 column array.
But the return X is a 2d arrary and returned y is a 1d array what is the reason for that?
So to put my quetion in one line:
what is the difference between
X = dataset.iloc[:, 0].values
and
X = dataset.iloc[:, :-1].values?
When I use:
X = dataset.iloc[:, 0].values
y = dataset.iloc[:, 1].values
X.shape
Out[207]: (30,)
y.shape
Out[204]: (30,)
When I use:
X = dataset.iloc[:, :-1].values
y = dataset.iloc[:, 1].values
X.shape
Out[203]: (30, 1)
y.shape
Out[204]: (30,)
python python-3.x pandas dataframe indexing
add a comment |
I have a dataset 30 obs and 2 columns i used code below to create independent and depend dataset for a single linear regression.
So each dataset is expected to be a 1 column array.
But the return X is a 2d arrary and returned y is a 1d array what is the reason for that?
So to put my quetion in one line:
what is the difference between
X = dataset.iloc[:, 0].values
and
X = dataset.iloc[:, :-1].values?
When I use:
X = dataset.iloc[:, 0].values
y = dataset.iloc[:, 1].values
X.shape
Out[207]: (30,)
y.shape
Out[204]: (30,)
When I use:
X = dataset.iloc[:, :-1].values
y = dataset.iloc[:, 1].values
X.shape
Out[203]: (30, 1)
y.shape
Out[204]: (30,)
python python-3.x pandas dataframe indexing
add a comment |
I have a dataset 30 obs and 2 columns i used code below to create independent and depend dataset for a single linear regression.
So each dataset is expected to be a 1 column array.
But the return X is a 2d arrary and returned y is a 1d array what is the reason for that?
So to put my quetion in one line:
what is the difference between
X = dataset.iloc[:, 0].values
and
X = dataset.iloc[:, :-1].values?
When I use:
X = dataset.iloc[:, 0].values
y = dataset.iloc[:, 1].values
X.shape
Out[207]: (30,)
y.shape
Out[204]: (30,)
When I use:
X = dataset.iloc[:, :-1].values
y = dataset.iloc[:, 1].values
X.shape
Out[203]: (30, 1)
y.shape
Out[204]: (30,)
python python-3.x pandas dataframe indexing
I have a dataset 30 obs and 2 columns i used code below to create independent and depend dataset for a single linear regression.
So each dataset is expected to be a 1 column array.
But the return X is a 2d arrary and returned y is a 1d array what is the reason for that?
So to put my quetion in one line:
what is the difference between
X = dataset.iloc[:, 0].values
and
X = dataset.iloc[:, :-1].values?
When I use:
X = dataset.iloc[:, 0].values
y = dataset.iloc[:, 1].values
X.shape
Out[207]: (30,)
y.shape
Out[204]: (30,)
When I use:
X = dataset.iloc[:, :-1].values
y = dataset.iloc[:, 1].values
X.shape
Out[203]: (30, 1)
y.shape
Out[204]: (30,)
python python-3.x pandas dataframe indexing
python python-3.x pandas dataframe indexing
edited Dec 31 '18 at 14:52
jpp
100k2161111
100k2161111
asked Dec 31 '18 at 14:40
Dongyang FuDongyang Fu
134
134
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
:-1 represents a range1, while -1 is a scalar. Ranges are 1-dimensional, while scalars are 0-dimensional. Think of a line versus a point; a range is a line while a scalar is a point. This is reflected in how Pandas translates a range vs scalar when indexing.
Therefore, the following are equivalent for a dataframe with 2 columns:
df = pd.DataFrame(np.random.random((5, 2)))
df.iloc[:, :-1].shape # (5, 1)
df.iloc[:, [0]].shape # (5, 1)
Using a scalar will remove the extra dimension. You can do this in a couple of ways:
df.iloc[:, 0].shape # (5,)
df.iloc[:, -2].shape # (5,)
In fact, :-1 is syntactic sugar for a slice object: slice(0, -1). In practice, the simpler syntax is preferred unless you need to pass slice objects around.
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53988637%2filoc-method-return-different-type-of-data%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
:-1 represents a range1, while -1 is a scalar. Ranges are 1-dimensional, while scalars are 0-dimensional. Think of a line versus a point; a range is a line while a scalar is a point. This is reflected in how Pandas translates a range vs scalar when indexing.
Therefore, the following are equivalent for a dataframe with 2 columns:
df = pd.DataFrame(np.random.random((5, 2)))
df.iloc[:, :-1].shape # (5, 1)
df.iloc[:, [0]].shape # (5, 1)
Using a scalar will remove the extra dimension. You can do this in a couple of ways:
df.iloc[:, 0].shape # (5,)
df.iloc[:, -2].shape # (5,)
In fact, :-1 is syntactic sugar for a slice object: slice(0, -1). In practice, the simpler syntax is preferred unless you need to pass slice objects around.
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
add a comment |
:-1 represents a range1, while -1 is a scalar. Ranges are 1-dimensional, while scalars are 0-dimensional. Think of a line versus a point; a range is a line while a scalar is a point. This is reflected in how Pandas translates a range vs scalar when indexing.
Therefore, the following are equivalent for a dataframe with 2 columns:
df = pd.DataFrame(np.random.random((5, 2)))
df.iloc[:, :-1].shape # (5, 1)
df.iloc[:, [0]].shape # (5, 1)
Using a scalar will remove the extra dimension. You can do this in a couple of ways:
df.iloc[:, 0].shape # (5,)
df.iloc[:, -2].shape # (5,)
In fact, :-1 is syntactic sugar for a slice object: slice(0, -1). In practice, the simpler syntax is preferred unless you need to pass slice objects around.
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
add a comment |
:-1 represents a range1, while -1 is a scalar. Ranges are 1-dimensional, while scalars are 0-dimensional. Think of a line versus a point; a range is a line while a scalar is a point. This is reflected in how Pandas translates a range vs scalar when indexing.
Therefore, the following are equivalent for a dataframe with 2 columns:
df = pd.DataFrame(np.random.random((5, 2)))
df.iloc[:, :-1].shape # (5, 1)
df.iloc[:, [0]].shape # (5, 1)
Using a scalar will remove the extra dimension. You can do this in a couple of ways:
df.iloc[:, 0].shape # (5,)
df.iloc[:, -2].shape # (5,)
In fact, :-1 is syntactic sugar for a slice object: slice(0, -1). In practice, the simpler syntax is preferred unless you need to pass slice objects around.
:-1 represents a range1, while -1 is a scalar. Ranges are 1-dimensional, while scalars are 0-dimensional. Think of a line versus a point; a range is a line while a scalar is a point. This is reflected in how Pandas translates a range vs scalar when indexing.
Therefore, the following are equivalent for a dataframe with 2 columns:
df = pd.DataFrame(np.random.random((5, 2)))
df.iloc[:, :-1].shape # (5, 1)
df.iloc[:, [0]].shape # (5, 1)
Using a scalar will remove the extra dimension. You can do this in a couple of ways:
df.iloc[:, 0].shape # (5,)
df.iloc[:, -2].shape # (5,)
In fact, :-1 is syntactic sugar for a slice object: slice(0, -1). In practice, the simpler syntax is preferred unless you need to pass slice objects around.
edited Dec 31 '18 at 14:51
answered Dec 31 '18 at 14:44
jppjpp
100k2161111
100k2161111
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
add a comment |
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
thx! I am new to python. I m a little crazy about how difficult it is to me. this helps so much!
– Dongyang Fu
Dec 31 '18 at 14:54
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53988637%2filoc-method-return-different-type-of-data%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown