form validation errors

There are two types of methods for showing form errors:

PHP Code:

<?php echo validation_errors(); ?> // shows all form errors

<form_open>

    <?php echo form_error('username'); ?> // only shows this error
    
</form> 


$this->form_validation->set_rules('name', 'name', 'trim|min_length[3]|numeric');

if( ! $this->form_validation->run()){
   echo validation_errors();
}

If the value of the field "name" will be "some text" I need you deduced error "min_length" and "numeric" and not just a mistake, "min_length".Thank you!