PHP installation Imagick extension problem: Is installed but does not have any method in the extension?

Phpinfo has seen a successful load of the imagick extension, but I'm using get_extension_funcs('imagick');But there is no way.
That's what I'm following:
First, use Yum to install the

yum install -y ImageMagick ImageMagick-devel

The installation was successful ImageMagick-6.5.4
Then install the PHP extension

phpize ./configure --with-php-config=/usr/local/php5.5/bin/php-config --with-imagick=/usr/make && make install

All goes well, but I don't have this method when I use a method in the Imagick extension.
Finally, using the get_extension_funcs('imagick'); function to see the method in this extension, but found nothing?

What is the reason for this?
Environment
Centos 6.5 + nginx1.4.7+php5.5

Reply content:

Phpinfo has seen the Imagick extension successfully loaded, but I get_extension_funcs('imagick'); don't have a way to use it.
That's what I'm following:
First, use Yum to install the

yum install -y ImageMagick ImageMagick-devel

The installation was successful ImageMagick-6.5.4
Then install the PHP extension

phpize ./configure --with-php-config=/usr/local/php5.5/bin/php-config --with-imagick=/usr/make && make install

All goes well, but I don't have this method when I use a method in the Imagick extension.
Finally, using the get_extension_funcs('imagick'); function to see the method in this extension, but found nothing?

What is the reason for this?
Environment
Centos 6.5 + nginx1.4.7+php5.5

You may need php -i |grep 'extension_dir' to run to see if there is a successful so file in the corresponding directory.
Then run php -i |grep 'ini' to find the INI configuration file location, go to add

[imagick]extension = so文件名

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