我是熊猫新手，所以希望这是一个简单的解决方法。我正在尝试创建一个仅包含df.loc []中调用的列的csv文件。我的csv文件当前显示所有可用的行/列，因此选择不起作用。
import requests, json
import pandas as pd
# url and date set earlier
response = requests.post(url, date, headers={'Authorization':'OAuth mycode'})
if response.status_code == requests.codes.ok:
response_json = response.json()
print('\n\n\nReturned JSON\n\n\n')
print(json.dumps(response_json, sort_keys=True, indent=4, separators=(',', ': ')))
# df = pd.DataFrame.from_dict(response_json)
df = pd.DataFrame(response_json)
print(df.keys())
df.loc[:,['Comment','EndTimeLocalized','Id','StartTimeLocalized']]
df.to_csv("r1.csv")
print('\nCSV Created\n')
else:
response.raise_for_status()
答案 0 :(得分：4)
pd.DataFrame.loc不是就地操作。
在导出前分配回df：
df = df.loc[:, ['Comment','EndTimeLocalized','Id','StartTimeLocalized']]
df.to_csv('r1.csv')
或者，如果您希望保持df不变，请在之后立即切片并导出：
df.loc[:, ['Comment','EndTimeLocalized','Id','StartTimeLocalized']].to_csv('r1.csv')
答案 1 :(得分：0)
另一种选择是在对function Get-DiskFree {
[CmdletBinding()]
param (
[Parameter(Position=0, ValueFromPipeline=$true, ValueFromPipelineByPropertyName=$true)]
[Alias('cn')]
[string[]]$ComputerName = $env:COMPUTERNAME,
[Parameter(Position=1, Mandatory=$false)]
[Alias('cr')]
[System.Management.Automation.Credential()]
$Credential = [System.Management.Automation.PSCredential]::Empty,
[Parameter(Position=2)]
[Alias('f')]
[switch]$Format
)
begin {
$ErrorActionPreference = "Stop"
function Format-HumanReadable {
param (
$size
)
switch ($size) {
{$_ -ge 1PB}
{"{0:#.#'P'}" -f ($size / 1PB); break}
{$_ -ge 1TB}
{"{0:#.#'T'}" -f ($size / 1TB); break}
{$_ -ge 1GB}
{"{0:#.#'G'}" -f ($size / 1GB); break}
{$_ -ge 1MB}
{"{0:#.#'M'}" -f ($size / 1MB); break}
{$_ -ge 1KB}
{"{0:#'K'}" -f ($size / 1KB); break}
default
{"{0}" -f ($size) + "B"}
}
}
$wmiq = 'SELECT * FROM Win32_LogicalDisk WHERE Size != Null AND DriveType >= 2'
}
process {
foreach ($computer in $ComputerName) {
try {
if ($computer -eq $env:COMPUTERNAME) {
$disks = Get-CimInstance -Query $wmiq -ComputerName $computer
}
else {
$disks = Invoke-Command -ArgumentList $wmiq { param($wmiq) Get-CimInstance -Query $wmiq } -ComputerName $computer -Credential $Credential `
| Select-Object DeviceID, DriveType, ProviderName, FreeSpace, Size, VolumeName
}
if ($Format) {
# Create array for $disk objects and then populate
$diskarray = @()
$disks | ForEach-Object { $diskarray += $_ }
$diskarray | Select-Object
@{Name='Name'; Expression={$_.SystemName}},
@{Name='Vol'; Expression={$_.DeviceID}},
@{Name='Size'; Expression={Format-HumanReadable $_.Size}},
@{Name='Used'; Expression={Format-HumanReadable (($_.Size)-($_.FreeSpace))}},
@{Name='Avail'; Expression={Format-HumanReadable $_.FreeSpace}},
@{Name='Use%'; Expression={[int](((($_.Size)-($_.FreeSpace))/($_.Size) * 100))}},
@{Name='FS'; Expression={$_.FileSystem}},
@{Name='Type'; Expression={$_.Description}}
}
else {
foreach ($disk in $disks) {
$diskprops = @{
'Volume'=$disk.DeviceID;
'Size'=$disk.Size;
'Used'=($disk.Size - $disk.FreeSpace);
'Available'=$disk.FreeSpace;
'FileSystem'=$disk.FileSystem;
'Type'=$disk.Description
'Computer'=$disk.SystemName;
}
# Create custom PS object and apply type
$diskobj = New-Object -TypeName PSObject -Property $diskprops
$diskobj.PSObject.TypeNames.Insert(0,'BinaryNature.DiskFree')
Write-Output $diskobj
}
}
}
catch {
# Check for common DCOM errors and display "friendly" output
switch ($_) {
{ $_.Exception.ErrorCode -eq 0x800706ba }
{$err = 'Unavailable (Host Offline or Firewall)'; break}
{ $_.CategoryInfo.Reason -eq 'UnauthorizedAccessException' }
{$err = 'Access denied (Check User Permissions)'; break}
default
{$err = $_.Exception.Message}
}
Write-Warning "$computer - $err"
}
}
}
end {
}
}
的调用中将列指定为关键字参数：
to_csv